I believe we have a thumb turn lock on our bathroom door. You twist the thumb lock bit from inside to lock the door and can see on the outside that the line is turned diagonally so can see it is locked.
However when you open the door from inside or outside when the door is locked, it unlocks itself!
Essentially it is pointless. Is it supposed to do this and does anyone know how to fix it please? I don't know what the lock was like when it was originally fitted as it was there before we moved into the house.