Yesterday I was also not able to use fingerprint after latest update I tried all possible try to register but failed. I am using tampered glass on my A50. You don't need to remove that. Because after using a50 from 5 or 6 months we are habitual of hard tapping on fingerprint sensor but now Samsung actually change the algorithms of fingerprint sensor. So here is my solution what I did. While registering your fingerprint make sure your thumb is clean. Now only tap gently/softly on finger print you will able to add fingerprint. Don't need to add two or three fingers for registering one fingerprint. Only tap gently on fingerprint you fingerprint will add.
I must say this time samsung actually improve fingerprint alot. Now it's working much better.
