Why isn't my fingerprint being recognized?

[AC Question]

Finger print not recognised dilemma

My wife has set up fingerprint security on her Samsung Galaxy Tab S2 , but now the tablet is not recognising her fingerprint. When she switches the tablet on, it displays the fingerprint not recognised message - enter backup password. Now she hasn't even scanned her fingerprint when this message appears, also she tells me she has not set up a backup password.
So how do we get to a position where the tablet asks to scan fingerprint and hopefully get it working again. I don't know if factory resetting would be an option, also don't know how to do this. I'd be reluctant to do a factory reset anyway as we bought the tablet in Hong Kong, and it will probably default to Chinese text.
So any help would be appreciated.

 

[B. Diddy]

Re: Finger print not recognised dilemma

Welcome to Android Central! You can't set up a fingerprint unlock without selecting a backup password (and then confirming it by entering it again). So she must have set up a backup password. One other possibility, though, is that you have a clone/knockoff device that isn't a genuine Samsung, and would therefore be more prone to firmware or hardware defects.