Recently my fingerprint hasn't been getting recognized and so I restarted my phone and deleted all my fingerprints to put them in again. When I started to add a fingerprint a couple lines would fill up like usual and then all of a sudden they would go back down again. No matter where I adjusted my finger they would just fill up a little and immediately go back down. I know that it sensed my finger was there because the lines would fill up a little when I put my finger there but then immediately go back down. My dad actually got his fingerprint to add after I showed him the problem but then when he tried unlocking my phone with it it still wouldn't work. He said that the way he got his fingerprint to add was that he barely touched the scanner. But when he tried it again and it wouldn't work.