Help Phone keeps asking for password instead of fingerprints

[jns20091]

My phone keeps asking for my password instead of letting me use fingerprint recognition to unlock my phone. Here is the exact message I am receiving:

"Enter password instead of using fingerprint recognition after restarting device to protect fingerprints"

I get this message inconsistently (not every time I unlock), about half the time. I was experiencing this issue with my Galaxy S6 Edge shortly before upgrading to the S7 Edge last week, and now I'm having it again. What would be causing this issue, and what can I do to fix it? Is it an app I downloaded? Software issue?

 

[girolez]

Hi

I have this occasionally. It is usually accompanied by a notification that I have an SD card available. There seems to be a soft reboot (Linux equivalent of as user logout) happening occasionally which requires the backup password rather than fingerprint to log in. The password is always required if the phone is powered off.

Note 4 with 6.0.1

 

[jns20091]

But my phone is doing this regularly throughout the day now. Also, it will randomly turn the screen off while I am using it, and then give me the same message, asking for the password instead of letting me use fingerprint recognition. The 'soft reboot' theory supports why the screen is being turned off randomly, and also wh8y I keep having to put in my password, but surely my brand spanking new phone doesn't need to soft reboot forty times a day? I will try to attach a screenshot of the message I am getting. Also, I am not receiving an additional notification about SD card availability, as suggested above.