might be greenify double tap hibernate+lock shortcut? you using that?

I asked this question a while back. In the end, I identified the issue from my lockscreen widget. Everytime I use the widget to lock screen, that issue happens.

The main "problem" comes back to the Smart Lock feature. Everytime it "hard-locks", you'll need to type pin regardless of fingerprint. So 2 ways to solve:

1) Set your frequent locations as trusted locations in Smart Lock in settings
2) Use the power button to lock and unlock instead of software lock like widgets.

Still holding tight my S7E coz it is an easy shooter though not like it oversharpen processing and SE5P as second phone