[gameplay] locked screen unlocks and refuses to lock

I always play with my screen locked on my champion, except in teamfights. I've noticed recently that my screen will occasionally unlock on its own and refuse to lock for a few minutes/until I die. This threw me off really bad and can be gamebreaking for people who play with their screen locked all the time. I can't reproduce the bug, it happens occasionally and there doesnt seem to be anything that triggers it.

1. I lock my screen
2. My screen unlocks
3. My screen refuses to lock for a minute or 2 or until i die
4. screen is locked again

I hope this issue can be resolved, since it's very annoying and potentially gamebreaking.