Lockscreen automatically relocks after unlock The Problem: Sometimes, after a successful screen unlock, the device immediately relocks.

Specifications: Nexus 9, CyanogenMod 12-12.1, Android 5.0.1-5.1.1, pattern lock and Smart Lock > FaceUnlock and Location active, encryption active.

Further details: I also have a phone (Armani) that ran exactly the same settings from CM 12-12.1 and experienced no such problems. This is weird, especially that flounder is officially supported while armani is not. The problem comes, on average, every other day. I'd like to know if anyone else had experienced similar problems and what you did to resolve it. So far all that I had to do is to reboot the device - something that ain't so nice especially on an encrypted device.
I had a similar problem with my Samsung Tab A 2019 Edition, that's how I fixed it:

Shutdown
Hold Vol Up and then Power on
It should say Secure Boot or sth like that
Log into your WLAN/WIFI/idkWhatItsCalled
Look for android updates and install if any
Edit Security Options or disable
Restart device