problem with front door UPVC lock?

If the lock is faulty you should change it as soon as possible.
You'll only need to replace the actual barrel, which costs less than a tenner.
To remove the lock barrel there is a single screw on the edge of the door at about keyhole level, though you might have to remove a cosmetic face plate first.
You may have to turn the key to remove the barrel.

Big Softy
March 2007