Samsung galaxy S21+5gno data or updates

[markroseuk]

Got above phone and no data WiFi is fine. Tried reset network and changing access point names but no joy. SIM works in a different phone

Also stuck on android 12 and says no updates. Been reset to factory several times.

[MI5]

@markroseuk 

Obvious question first - where did the phone come from?

If it won't auto update it's possible that someone has flashed different firmware in the past so you'll have to do the same to update it.