Did someone notice that whenever you were on the spotify and the wireless earphones is connected you cannot use the face unlock?
Because you probably have smart lock on
If you add a place,your BT headphones as a trusted agent the phone will be unlocked as long it's connected to that headphone.
Btw I have added those two as trusted agents
See the bottom text
The phone is already unlocked when smart lock is on (whenever it's connected to either of my two devices)
You probably have smart lock on
It'll keep the device unlocked as long as the bt devices you selected are connected to your phone
Btw smartlock is in the security and lock screen section in settings