Mitsubishi Repair: 99 Carisma Tailgate lock problem, mitsubishi carisma, lubricant spray

Question
Hi, my mother in law has just acquired a very nice V reg Mitsubishi carisma, although the car is fairly tidy throughout and a good runner, we have found that there seems to be a fault with the tailgate, which will not lock. The central locking unit works fine but even when the car should be locked the tailgate still opens from the button outside regardless of whether it is in the locked position or not. Is this a common problem and what would you advise as the best course of action to repair? Thanks, any help is greatly appreciated :) A Bedford.

Answer
Ainsley,
You may just have a sticky locking mechanism in the tailgate.  You can try to look for anything in the locking mechanism that may be obstructing, plus you can try spraying some lubricant spray in there to help get the parts moving again.  Else, you'll want to have a mechanic inspect the lock and replace if necessary.
Good luck!