I have this basic door locking system where you can only lock the door from one side.
However since I am using ProximityPrompts with RequiresLineOfSight Enabled players can zoom behind the door and activate the proximity prompt. I’m sure there’s a fix for this by just preventing the camera from noclipping through the door. I’m pretty sure it’s happening because parts of my door are unanchored.
You said you are pretty sure this happens cos the parts are unanchored. Have you tried anchoring the parts?
(I think it’s because your windows are transparent. Try making the door solid. If that fixes the problem but you sill want the door to be glass, I belive there is a post around here somewhere that solved that issue. Ill find it for you if you need it.)