It hit me this morning - Note 5 on Sprint. Updated the OS to v 6.0 I think it said... after it finished and rebooted I'm locked out.
when the phone was new I got locked out (a few friends too) of the fingerprint lock a few times - and wouldn't accept the backup code... At least then it gave me the option to get it using my google login.
This time it won't take my pattern, code, and not even an option to use my google account...
Spent FOUR HOURS on the phone & chat with Sprint, Google, and Samsung on this... everyone kept passing the blame until the last Samsung rep that I got through google -- he finally said it was Samsung's fault - which it obviously is, they take android from google and tweak it, then THEY push it onto us...
No resolution either... just the shortcut answer that I have to do a hard reset.