fingerprint sensor erratic

[mischka1]

Hello

I just bought an XA2 a few days ago and the fingerprint sensor is behaving strangely, After a while it won't unlock the phone anymore, as if some software component crashed. I can still see it in the settings but I can't register new fingerprints. 
However, if I just put the phone away without pressing the power button and letting it lock itself, I can then unlock it by fingerprint. In other words, actively locking it prevents the fingerprint sensor from working. And no, I didn't use the lockdown option!
Restarting the phone fixes the problem. Once I reboot it, the sensor works again and unlocks the phone. But that's not a solution. 

I have android 9 

thanks for your attention

[Revsky]

Same problem

[Kinkong78]

Same hear my battery went flat so I had to reset my finger print pattern it won't let me complete the pattern saying it does not recognise my finger print and before the battery died it would not recognise my print not all the time when it di it could take upto twenty seconds for it to boot up and some times it just won't recognise my print its like it went over sensertive as it would vibrate before you touched the sensor then it would not work as it would not as I had not even got to touch it lol all this happened after the last but one update it worked great before that update so Iam going to try a factory reset and try again and see what happens.