hi, pretty sure some skank has tried to get into my house via the upvc french doors. the left door locks at top and bottom via two latches on the side and the right door locks at the top middle and bottom via the lock. the key functions in the lock ok, turning all the way left and right but the door will not open. when i turn the key to the locked position it does not seem to lock at the top. when i unlock there is no play in the middle or bottom which makes me think it's locked in the middle and bottom all of the time. i don't think it can be the lock itself and am thinking it might be the mechanism on the side of the door but how can i get the door open to check it out. sorry if this seems long but i've tried to explain in detail what is happening. thanks, mark