Mobile Data issue after One UI 3.1 + Android 11 Update

[Vevaphon]

Hi there, my A71 had the recent 3.1 + 11 update go in and now has an issue where I can no longer use mobile data properly.

On WIFI everything works fine, but off WIFI I have no internet connection, Chrome can't load pages, other (non-Google) Apps open but can't load any information etc. The only thing that does still work is Facebook Messenger for some reason. My phone still shows I'm connected to my network (Three) 4G+ and plenty of signal etc.

Is there anything obvious I'm missing that would cause this or be a fix?

[Jaz04]

Have you checked your APN settings? They might have reset somehow

[Vevaphon]

As far as I can tell the APN settings are as expected with Three, the only difference being the APN Type line listing 'default,supl,mms,xcap,email' as opposed to reading 'internet + mms' which is what guides online show. However I can't actually edit this type line and if I try and add another APN with those settings the phone won't allow me to change to that one, I'm assuming because of the default clause in the existing APN.

[JohnM2]

I too have this problem on 3 after updating my phone today.

[Jaz04]

Is it due to the issue with the android system webview thing?

[Vevaphon]

Not as far as I can tell, symptoms don't seem to match. On WIFI everything works just fine, off and apps will load but they don't crash, just state that there's no internet connection / won't load any content, state that you're offline etc.

[Jaz04]

Have you tried a force reboot?

[Vevaphon]

Everything shy of a factory reset so far with no changes unfortunately.

[Jaz04]

So you've performed a force reboot and nothing helped?

[Jaz04]

This is what one of my mates told me to do with my old HTC device when it was playing up with my 3 sim card:

Before rebooting, turn on Airplane Mode.
Wait for 30 seconds, then turn Airplane Mode off.
If you still don't have data, turn airplane mode back on, turn your phone off, wait for a minute, turn your phone back on, turn airplane mode off,
wait for thirty seconds, then turn mobile data on.
Check if it works