Hi and welcome to the community and its forum.
Maybe we could start with a few basic items:
- Could you indicate your OS version. Go to
Settings > About phone > Build number
That should be FP5.TT4F.A.160.20240508 if you’re on the latest. - Are you using a SD card in the phone? This can cause problems if you’re saving photos to the card.
- What app are you using for navigation?
As for a reset, yes unfortunately you may be right, but you would have to do that anyway if the phone has to be sent back. So the first thing to do is to make sure you have proper backups of your files and other data, especially contacts and messages.
I’ve seen at least three other cases of fingerprint sensor not working recently. Have a look.