Fingerprints don't unlock the phone

[MinervApollo]

Greetings and blessings. My Sony Xperia Z5 (regular version, not Compact or Premium) works beautifully as intended in almost every way. I have a couple of fingerprints registered, which I use for unlocking my phone. However, for some reason, whenever the device is locked (i.e. Smart Lock detects the phone has been set down), when I try to use my fingerprint to unlock the phone, it is read correctly, but immediately brings up the PIN/pattern/password input screen. This happens every time if the phone is locked. I'd like to emphasize that the fingerprints are not being read correctly, because the phone still vibrates agrafter an incorrect check.  I've tried to restart the phone and change the unlocking methods to no avail.  If it  is relevant, I mainly lock the phone using an Assistive Touch application. 

I'd greatly appreciate your help, and thank you for your time. 

[Christofer · Accepted solution]

Hi @MinervApollo,

Does it behave the same way if you lock your phone by pressing the power key, or if you test this in safe mode?

If the screen is locked or turned off using a third-party app you can't unlock your device using the fingerprint sensor. This is caused by the strong authentication requirements of the Smart Lock feature in Android 6.0 and works as designed.

[MinervApollo]

Thank you! I did what you told me, and it worked. I didn't know it worked like that. I guess no more Assistive Touch for me! Many blessings for you.

[Christofer]

You're welcome!

[StevieO]

Hi There Sony

I recently did a facroty reset on my Xperia X,when it supposed to start my phone automatically locks itself and the screen becomes blank and when I connect it to my Xperia Companion it says my device is locked....So im not sure if my fingerprint scanner button is broekn or not though it allows me to do a reboot but thats about it...please help me asap