Same issue, my phone just quite accepting my pin number. Wouldn't unlock at all and trying to reset wouldn't accept my gmail accouant. Verizon sending me a new phone. They couldn't get it to restart either. Wish I had found this site sooner.....
Today I tried to Factory Reset but that needed my PIN - which I DID NOT HAVE - i then had to wait 60 minutes to retry.
In the mean time I got a notice that a system update was available - I envoked this and waited for the download and installation and reboot and then ----- My PIN again worked !!!!
My wife phone having the same issue. She kept trying and the phone got reset. Now all pictures, videos and other personal stuff are gone. Is there away to get these pictures back???
My S7 just got an updated lock screen app from Samsung and after the reboot (which means I cannot use the fingerprint) it is not accepting my PIN. I tried a hard power off/power on and still it does not accept my PIN. Now it warns that if I fail two more attempts the phone will be wiped?? Almost seems like that app update was malicious.
I can't use the findmymobile site because my phone was apparently never registered.
I feel pretty well stuck between a rock and a hard place.
You have 3 options. If all of them fail you will have to factory reset the phone hence wiping all data.
Finger print reader. Pin/password, and findmymobile.
I can only suggest to restart the phone in recovery mode. Clear phone cache and restart. See if that helps.
Of course if the carrier has a way to unlock it for you I would go there first.
I was forced to wipe and reset mine in the course of trying more self-troubleshooting.
One particularly notable failure was with the Google Android Device Manager - it found my phone just fine and even semi-successfully overrode the lock screen, but as soon as I touched the phone and removed the Device Manager's lock, the phone's lock screen STILL came up and requested a PIN.
Thankfully I had cloud backups with both google and verizon so recovery hasn't been an unmitigated nightmare.
Of course, even though I am now fully registered on the findmymobile site, I am now too paranoid of this issue to use any kind of lock screen security at all now, so this has been a winning occasion all around!
Considering another user posted steps to actually replicate the problem earlier in this very thread, I also find it pretty disappointing that there is no official acknowledgment of an issue or any assurance of even research towards a fix.