Android system updates normally improve security, stability, compatibility, and performance. However, after installing an Android update, some users may suddenly discover that mobile data has stopped working, even though phone calls and SMS continue to work normally.

Typical symptoms include:

• Mobile data is enabled but there is no internet.
• 4G, LTE, 5G, or VoLTE/VoNR indicator disappears.
• The phone shows signal bars but websites do not open.
• Mobile data repeatedly connects and disconnects.
• The device remains stuck on EDGE, E, 2G, or 3G.
• 5G worked before the update but no longer works.
• "No Internet Connection" appears.
• Apps work on Wi-Fi but not on mobile data.
• The SIM is detected but cellular internet does not work.
• Mobile data works on one SIM but not another.
• Calls work normally while data does not.
• The phone shows 4G/5G but there is still no internet.
• Internet becomes unusually slow after the Android update.

In many cases, the problem is caused by changed APN settings, network configuration, SIM preferences, carrier settings, preferred network mode, VPN settings, Private DNS, or corrupted network configuration rather than a physical failure of the phone.

This guide explains how to troubleshoot mobile-data problems safely and systematically.

1. Why Can Mobile Data Stop Working After an Android Update?

Android updates can modify several components responsible for cellular connectivity.

These may include:

• Android networking services
• Cellular modem configuration
• Carrier profiles
• APN configuration
• SIM management
• 4G/LTE configuration
• 5G configuration
• IMS services
• VoLTE/VoNR configuration
• DNS handling
• VPN compatibility
• Network security policies
• Power-management settings
• Carrier-specific software

A configuration that worked correctly before the update may therefore need to be refreshed or recreated.

2. First Check Whether Mobile Data Is Actually Enabled

Before performing advanced troubleshooting, verify that mobile data is switched on.

Depending on the Android manufacturer, look under:

Settings → Network & Internet → SIMs → Mobile Data

or:

Settings → Connections → Data Usage → Mobile Data

or:

Settings → Mobile Network → Mobile Data

Make sure Mobile Data is enabled.

The exact menu names vary between Samsung, Google Pixel, OnePlus, Motorola, Xiaomi, Redmi, POCO, Nothing, Vivo, Oppo, Realme and other Android devices.

3. Turn Airplane Mode On and Off

This is one of the easiest ways to force Android to reconnect with the cellular network.

1. Enable Airplane Mode.
2. Wait approximately 20–30 seconds.
3. Disable Airplane Mode.
4. Wait for the cellular signal to return.
5. Test mobile data again.

This forces the cellular radio to disconnect and register again with the network.

4. Restart the Android Phone

After an Android upgrade, some networking services may not initialize correctly until another reboot.

Restart the phone normally.

After restart:

1. Wait for the SIM to register.
2. Confirm signal bars appear.
3. Enable mobile data.
4. Test a website or application.

Do not immediately assume that the update damaged the phone.

5. Check Signal Strength

Look at the cellular signal indicator.

If the device shows:

• No Service
• Emergency Calls Only
• Searching
• SOS
• No SIM

then the issue may not be limited to mobile internet.

Move to an area where the carrier normally provides reliable coverage.

If calls and SMS also fail, investigate the SIM, carrier network, account status, device registration, or radio connectivity first.

6. Check Whether the Carrier Has an Outage

An Android update may simply coincide with a temporary carrier outage.

If possible:

• Check another phone using the same carrier.
• Ask another user nearby.
• Contact your carrier.
• Check the carrier's official service-status information.

If multiple customers are experiencing the same issue, changing Android settings may not solve anything.

7. Check Your Mobile Data Plan

Confirm that the SIM has:

• An active cellular plan
• Remaining data allowance
• No billing restriction
• No expired recharge
• No data suspension
• No carrier-side restriction

For prepaid connections, check whether the required recharge or data pack is active.

8. Verify the Correct SIM Is Selected for Mobile Data

This is particularly important on dual-SIM Android phones.

After an update, the preferred SIM settings may change.

Open:

Settings → SIM Manager / SIMs / Mobile Network

Check which SIM is configured for:

• Mobile data
• Calls
• SMS

If SIM 1 contains your active internet plan but Android is attempting to use SIM 2 for data, mobile internet may fail.

Select the correct SIM as the preferred Mobile Data SIM.

9. Disable and Re-enable the SIM

Some Android devices allow individual SIMs to be temporarily disabled.

Go to:

Settings → SIMs / SIM Manager

Disable the affected SIM.

Wait approximately 20 seconds.

Enable it again.

Allow the phone to register with the network and test mobile data.

10. Check the APN Settings

The Access Point Name (APN) tells Android how to connect to the carrier's mobile-data network.

An Android update may reset, replace, disable, or incorrectly modify an APN.

Typical location:

Settings → Mobile Network → SIM → Access Point Names

or:

Settings → Network & Internet → SIMs → Access Point Names

Verify that the correct carrier APN is selected.

APN parameters can include:

• Name
• APN
• Proxy
• Port
• Username
• Password
• Server
• MMSC
• MMS proxy
• MCC
• MNC
• Authentication type
• APN type
• APN protocol
• APN roaming protocol

Do not enter random APN values found on unverified websites.

Obtain the correct APN settings from your mobile operator.

11. Reset the APN to Default

If you are unsure whether the APN is correct, resetting it may be safer than manually modifying multiple parameters.

Open:

Settings → Mobile Network → Access Point Names

Open the menu and select:

Reset to Default

Restart the phone afterward.

Android should reload the carrier's standard APN configuration where supported.

12. Create a New APN Manually

If resetting the APN does not restore mobile data, obtain the official APN configuration from the carrier.

Select:

Access Point Names → Add APN

Enter the carrier-provided values exactly.

Save the APN and select it.

Restart the phone and test mobile data.

Incorrect MCC, MNC, APN type, protocol, authentication, or APN values can prevent mobile internet from working.

13. Check Preferred Network Type

An Android update can sometimes change the preferred network mode.

Navigate to:

Settings → Mobile Network → Preferred Network Type

Depending on the phone and carrier, options may include:

• 5G/4G/3G/2G Auto
• 5G/LTE
• LTE/3G/2G
• 4G/3G/2G
• LTE only
• 3G
• 2G

For normal usage, an automatic mode such as:

5G/4G/3G/2G Auto

is generally preferable where supported.

Avoid forcing a network technology unless you have a specific troubleshooting reason.

14. 5G Not Working After Android Update

If only 5G has stopped working but 4G works, check:

Settings → Mobile Network → Preferred Network Type

Make sure 5G is enabled.

Also verify:

• Your SIM supports 5G.
• Your plan includes 5G access.
• 5G coverage exists in your location.
• The carrier supports your device.
• Battery-saving features are not restricting 5G.
• The phone's network mode was not changed by the update.

If necessary, temporarily select 4G/LTE and check whether mobile data works.

If LTE works but 5G does not, the issue is more specifically related to 5G registration, coverage, provisioning, configuration, or compatibility.

15. Temporarily Switch from 5G to 4G

For troubleshooting, select:

LTE/4G

instead of 5G.

Then test mobile data.

If internet works correctly on 4G, the SIM and APN are probably at least partially functional.

The issue may involve:

• 5G carrier provisioning
• 5G coverage
• Modem firmware
• Carrier profile
• Network compatibility
• Post-update 5G configuration

You can switch back to automatic 5G later.

16. Check Data Roaming

If you are outside your carrier's normal network area, mobile data may require roaming.

Go to:

Settings → Mobile Network → Data Roaming

Enable it only if appropriate for your plan.

Warning: Data roaming can result in additional charges, particularly during international travel. Confirm your carrier's roaming charges before enabling it.

17. Disable VPN Temporarily

VPN applications can interfere with connectivity after an Android update, particularly if the VPN application or its network driver/configuration is incompatible with the new Android version.

Temporarily disconnect the VPN.

Then test mobile data.

If mobile data starts working, update or reconfigure the VPN application.

Also check:

Settings → Network & Internet → VPN

Look for options such as:

• Always-on VPN
• Block connections without VPN

If "Block connections without VPN" is enabled and the VPN cannot connect, the phone may appear to have no internet.

18. Check Private DNS

Incorrect Private DNS configuration can make mobile data appear completely broken.

Go to:

Settings → Network & Internet → Private DNS

Temporarily choose:

Automatic

or, for testing:

Off

Then test mobile data again.

If internet starts working, investigate the previously configured DNS provider.

19. Check Whether Only Certain Apps Are Affected

If Chrome works but WhatsApp does not—or vice versa—the cellular network itself may not be the problem.

Check:

Settings → Apps → [App Name] → Mobile Data & Wi-Fi

Ensure the application is permitted to use:

• Mobile data
• Background data
• Unrestricted data, if required

Manufacturer-specific Android versions may provide additional per-application network restrictions.

20. Disable Data Saver Temporarily

Data Saver can restrict background data and certain application behavior.

Open:

Settings → Network & Internet → Data Saver

Temporarily disable it.

Test the affected applications again.

If this fixes the issue, review which applications have unrestricted data access.

21. Check Mobile Data Limit

Android can disable or warn about mobile data after reaching a configured usage limit.

Check:

Settings → Network & Internet → SIM → Data Warning & Limit

or:

Settings → Connections → Data Usage → Billing Cycle and Data Warning

Check whether:

• A data limit is enabled.
• The configured limit has been reached.
• The billing-cycle date is correct.

Disable or adjust the limit if appropriate.

22. Check Battery Saver

Aggressive battery-saving features can restrict background network activity.

Temporarily disable:

Battery Saver / Power Saving Mode

Then test mobile data.

Some manufacturers also provide application-specific battery optimization.

If only one application is affected, check:

Settings → Apps → [App] → Battery

and review its background usage settings.

23. Reset Mobile Network Settings

One of the most effective solutions after an Android update is resetting network configuration.

Depending on your phone:

Settings → System → Reset Options → Reset Mobile Network Settings

or:

Settings → General Management → Reset → Reset Mobile Network Settings

Some devices provide a combined option such as:

Reset Wi-Fi, Mobile & Bluetooth

This can reset:

• Cellular network configuration
• APN-related configuration
• Wi-Fi settings
• Bluetooth configuration
• Network preferences

Important

Depending on the manufacturer and Android version, saved Wi-Fi networks, paired Bluetooth devices, VPN/network preferences, and other network configuration may need to be configured again.

Read the confirmation screen carefully before proceeding.

24. Restart the Phone After Network Reset

After completing a network reset:

1. Restart Android.
2. Wait for SIM registration.
3. Enable mobile data.
4. Verify the correct data SIM.
5. Check the APN.
6. Test the internet.

This allows Android to rebuild the cellular configuration.

25. Remove and Reinsert the Physical SIM

Turn off the phone before removing the SIM where recommended by the device manufacturer.

Remove the SIM card and inspect it for:

• Dirt
• Damage
• Incorrect positioning
• Poor contact

Reinsert it correctly and restart the phone.

If the phone uses an eSIM, do not delete the eSIM merely as an initial troubleshooting step.

Deleting an eSIM may require carrier assistance or a new activation process.

26. Test the SIM in Another Phone

This is an extremely useful diagnostic step.

Insert the affected SIM into another compatible unlocked phone.

If mobile data works in the second phone:

The problem is likely related to the original phone, its configuration, software, carrier profile, or compatibility.

If mobile data also fails in the second phone:

The problem may involve:

• SIM provisioning
• Carrier account
• Data plan
• SIM failure
• Carrier outage

Contact the carrier.

27. Test Another Working SIM in the Updated Phone

If possible, place another known-working SIM into the affected phone.

If the second SIM works:

The original SIM, APN, plan, or carrier provisioning is more likely responsible.

If no SIM can access mobile data:

The updated phone's software, network configuration, modem firmware, or hardware becomes more suspect.

This cross-testing method is much more informative than repeatedly changing random settings.

28. Check for Another Android Update

Sometimes a major Android release introduces a connectivity bug that is subsequently corrected through another update.

Check:

Settings → System → Software Update

or:

Settings → Software Update

Install any newer stable update officially provided for your device.

Also check for Google Play system updates where available.

29. Update Carrier-Related Apps and Services

Some Android phones depend on carrier-related services or system components distributed through Google Play or the manufacturer's app store.

Open the app store and install pending updates, particularly for:

• Carrier-related services
• Google system components
• Manufacturer system applications

Restart the device afterward.

30. Clear Cache of Carrier-Related Components Carefully

On some devices, clearing the cache—not necessarily the stored data—of relevant carrier or SIM-related system applications can help.

However, system component names differ significantly between Android manufacturers.

Avoid indiscriminately clearing storage/data from critical system applications unless you understand its function.

A safer first approach is:

1. Restart.
2. Reset APN.
3. Reset network settings.
4. Install updates.
5. Contact the carrier.

31. Check Date and Time

Incorrect date and time can cause HTTPS, authentication, VPN, application, and certificate problems that resemble an internet failure.

Open:

Settings → System → Date & Time

Enable:

• Set time automatically
• Set time zone automatically

Then test the connection again.

32. Check Whether Calls and SMS Work

This helps isolate the problem.

Calls + SMS + Data all fail

Possible causes:

• SIM problem
• Network outage
• SIM registration problem
• Device radio issue
• Carrier account restriction

Calls and SMS work, but mobile data fails

More likely causes include:

• Incorrect APN
• Data plan issue
• Wrong data SIM
• Network mode
• Data restriction
• VPN
• DNS configuration
• Carrier provisioning

33. Mobile Data Shows 4G/5G but Internet Does Not Work

This symptom can be confusing.

The cellular icon only indicates that the device has registered with a particular network technology. It does not guarantee that usable internet connectivity exists.

Possible causes include:

• Incorrect APN
• DNS failure
• VPN problem
• Carrier routing issue
• Data-plan restriction
• Network outage
• Authentication/provisioning issue

Try opening multiple websites and applications.

Temporarily disable VPN and Private DNS before concluding that cellular data itself has failed.

34. Mobile Data Works but Is Extremely Slow After Update

If data works but performance is poor:

1. Check signal strength.
2. Switch temporarily from 5G to LTE/4G.
3. Disable VPN.
4. Disable Data Saver.
5. Check your data allowance.
6. Restart the phone.
7. Reset APN settings.
8. Reset mobile network settings.
9. Test the SIM in another phone.
10. Compare speed at another location.

Network congestion can also produce slow speeds and may have nothing to do with the Android update.

35. Dual-SIM Problems After Android Update

Dual-SIM devices require additional checks.

Verify:

• Correct SIM selected for data
• Both SIMs are detected
• Preferred network mode for each SIM
• Data switching configuration
• Roaming settings
• APN configuration for the selected data SIM

For troubleshooting, you can temporarily disable the secondary SIM and test only the primary data SIM.

36. eSIM Mobile Data Not Working After Update

If you use an eSIM:

1. Confirm the eSIM is enabled.
2. Verify it is selected for mobile data.
3. Check the APN.
4. Toggle Airplane Mode.
5. Restart the phone.
6. Reset mobile network settings.
7. Contact the carrier if the eSIM profile appears inactive or incorrectly provisioned.

Avoid deleting the eSIM profile unless your carrier or device manufacturer specifically recommends it and you have a reliable method to reactivate it.

37. Try Safe Mode

If mobile data fails because of a third-party application, Safe Mode can help isolate the cause.

Safe Mode temporarily disables most downloaded applications.

If mobile data works correctly in Safe Mode, investigate recently installed or updated applications such as:

• VPN software
• Firewall applications
• Ad blockers
• Security applications
• DNS changers
• Network-monitoring applications
• Battery-management tools

The procedure for entering Safe Mode varies by manufacturer.

38. Reset App Preferences

If important system services or permissions were accidentally disabled, resetting app preferences may help.

Typically:

Settings → Apps → Reset App Preferences

This may restore:

• Disabled applications
• Default applications
• Permission-related preferences
• Background restrictions
• Notification preferences

Review the confirmation message because behavior differs among Android versions.

39. Do Not Factory Reset Too Early

A factory reset should not be the first solution.

Before factory resetting, try:

1. Airplane Mode
2. Restart
3. Correct data SIM
4. APN reset
5. Preferred network mode
6. VPN/Private DNS checks
7. Data limit check
8. Network settings reset
9. SIM cross-testing
10. Carrier verification
11. Newer software update
12. Safe Mode

Factory reset should normally be considered only after simpler troubleshooting fails.

40. Back Up Your Data Before Factory Reset

A factory reset removes user data from the device.

Back up important information such as:

• Photos
• Videos
• Contacts
• Documents
• WhatsApp/chat data where applicable
• Authenticator/recovery information
• Application data
• Notes
• Downloads
• Device settings

Also make sure you know the Google account credentials associated with the phone before resetting it.

41. Factory Reset Android

If mobile data worked before the Android update and every other troubleshooting step has failed, a factory reset may help eliminate corrupted configuration left behind after the upgrade.

Typically:

Settings → System → Reset Options → Erase All Data

or:

Settings → General Management → Reset → Factory Data Reset

Menu names differ between manufacturers.

After resetting, consider testing mobile data before reinstalling all third-party applications. This helps determine whether the clean Android installation works correctly.

42. Contact the Mobile Carrier

Contact your mobile network provider when:

• SIM works for calls but never for data.
• APN settings appear incorrect or unavailable.
• SIM fails in another phone.
• 5G provisioning has disappeared.
• Carrier authentication fails.
• Account provisioning may be incorrect.
• A replacement SIM may be required.

Ask the carrier to verify:

• Data service status
• SIM provisioning
• APN settings
• 4G/LTE provisioning
• 5G provisioning
• Account restrictions
• Network outage
• Device compatibility

43. Contact the Phone Manufacturer

Contact the manufacturer if:

• Multiple working SIMs fail in the phone.
• The issue started immediately after an official update.
• Network reset does not help.
• Factory reset does not help.
• Other users of the same device model report similar problems.
• The modem/baseband appears abnormal.
• The SIM is intermittently detected.

The manufacturer may have a device-specific patch or service procedure.

44. Check Baseband Information

Advanced users can check:

Settings → About Phone → Android Version / Software Information

Look for the Baseband Version.

If baseband information is missing or shown as Unknown, and the phone also cannot properly detect cellular networks, this can indicate a more serious modem firmware or hardware issue.

Do not flash random modem or firmware packages obtained from unofficial sources.

Incorrect firmware flashing can make the device unusable or create additional radio/network problems.

45. Recommended Troubleshooting Order

For the safest and fastest diagnosis, follow this sequence:

Step 1: Confirm mobile data is enabled.

Step 2: Enable and disable Airplane Mode.

Step 3: Restart Android.

Step 4: Confirm an active mobile-data plan.

Step 5: Check the correct SIM is selected for data.

Step 6: Verify network coverage.

Step 7: Reset APN to default.

Step 8: Check preferred network type.

Step 9: Temporarily disable VPN and Private DNS.

Step 10: Check Data Saver and data limits.

Step 11: Reset mobile network settings.

Step 12: Test the SIM in another phone.

Step 13: Test another SIM in the affected phone.

Step 14: Check for another Android/system update.

Step 15: Contact the carrier.

Step 16: Test Safe Mode.

Step 17: Back up data.

Step 18: Consider factory reset.

Step 19: Contact the device manufacturer or authorized service center if the issue continues.

Diagnostic Table

Symptom	Possible Cause	Recommended Check
Signal available but no internet	APN/DNS/VPN	Reset APN, disable VPN/Private DNS
Calls work but data does not	APN or provisioning	Check APN and carrier account
No signal	SIM/network/radio issue	Reinsert SIM and check carrier
5G disappeared	Network mode/provisioning	Check 5G settings and carrier
4G/5G icon but no internet	APN/DNS/routing	Test APN, VPN and Private DNS
Data works on Wi-Fi only	Cellular configuration	Reset mobile network
One SIM works, another does not	SIM/APN/carrier	Cross-test SIMs
Another SIM also fails	Phone/software issue	Network reset/manufacturer
SIM works in another phone	Device configuration	Troubleshoot updated phone
SIM fails in another phone	Carrier/SIM issue	Contact mobile operator
Only some apps fail	App data restriction	Check per-app data permissions
Data is extremely slow	Coverage/congestion/network mode	Test LTE/4G and another location

Frequently Asked Questions (FAQ)

1. Why did mobile data stop working after an Android update?

An update may modify APN settings, carrier profiles, network preferences, SIM configuration, VPN compatibility, DNS behavior, modem software, or other cellular settings.

2. Can an Android update reset APN settings?

Yes. Depending on the device and carrier, an update or network configuration refresh can alter or replace APN settings.

3. What is an APN?

APN stands for Access Point Name. It defines how your Android phone connects to your mobile carrier's packet-data network.

4. Should I manually change the APN?

Only if you have the correct settings from your carrier. Incorrect APN parameters can prevent mobile data from working.

5. Why do calls work but mobile data does not?

Voice and data services can have different configuration and provisioning requirements. An incorrect APN, data-plan restriction, or carrier provisioning problem can affect data while calls still work.

6. Why does my phone show 5G but there is no internet?

The 5G indicator does not guarantee successful internet routing. APN, DNS, VPN, provisioning, carrier outages, or account restrictions can still prevent connectivity.

7. Should I switch from 5G to 4G?

It is a useful temporary diagnostic step. If 4G works but 5G does not, investigate 5G coverage, settings, provisioning, or compatibility.

8. Will resetting network settings delete my photos?

Normally, no. A network reset is different from a factory reset. However, it may remove saved network-related settings such as Wi-Fi and Bluetooth configuration depending on the device.

9. Will resetting APN delete my personal data?

No. Resetting APN settings does not normally delete photos, documents, contacts, or other personal files.

10. Can a VPN stop mobile data?

Yes. A malfunctioning VPN, Always-on VPN, or "Block connections without VPN" configuration can make it appear that mobile internet is unavailable.

11. Can Private DNS cause this problem?

Yes. If the configured Private DNS server is unreachable or incorrectly configured, websites and applications may fail even though cellular connectivity exists.

12. Why does Wi-Fi work but mobile data not work?

This usually points toward the SIM, APN, cellular configuration, carrier network, account, or mobile-data restrictions rather than a general Android internet problem.

13. Should I remove my eSIM?

Not as an early troubleshooting step. Deleting an eSIM can require carrier reactivation. Try less destructive troubleshooting first.

14. How can I determine whether the SIM or phone is faulty?

Put the SIM in another compatible phone and test another working SIM in your phone. Cross-testing is one of the best ways to isolate the problem.

15. Can Data Saver disable internet?

It can restrict certain applications and background data. Temporarily disabling Data Saver is useful for testing.

16. Can Battery Saver affect mobile data?

It can restrict background network activity or application behavior on some Android devices.

17. Why did my mobile data become slow after the update?

Possible causes include changed network mode, weak coverage, network congestion, VPN overhead, background activity, carrier throttling, or modem/software changes.

18. Should I factory reset immediately?

No. Factory reset should normally be one of the final troubleshooting steps after APN, network reset, SIM testing, carrier checks, and software updates have been attempted.

19. Will factory reset fix mobile data?

It can fix problems caused by corrupted Android settings or software configuration, but it will not fix carrier outages, account restrictions, defective SIM cards, or physical hardware faults.

20. What should I do if mobile data still does not work after factory reset?

Cross-test the SIM and phone, contact your carrier to verify provisioning, and contact the phone manufacturer or authorized service center if multiple working SIMs fail in the device.

Conclusion

Mobile data failing immediately after an Android update does not necessarily mean that the phone's cellular hardware has failed.

In many cases, the problem can be resolved by restarting the device, refreshing the cellular connection, selecting the correct data SIM, resetting the APN, checking the preferred network mode, disabling problematic VPN or Private DNS settings, resetting network settings, or correcting carrier provisioning.

The most important diagnostic technique is cross-testing: test the affected SIM in another phone and test another known-working SIM in the updated phone. This quickly helps determine whether troubleshooting should focus on the mobile carrier/SIM or the Android device itself.

Avoid factory resetting or manually flashing firmware until safer troubleshooting methods have been exhausted.

 

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