1994 Honda Accord doors wont lock

Other Category problem
1994 Honda Accord 4 cyl Wheel Drive Type unknown Automatic 140000 miles

I lock my drivers side door outside with my key, test to make sure it is locked then come back an hour later to find that is open, then I tried pushing down on the master lock before closing, door locks but not permantely, then I tried locking it from the insdie with the lock button, door still ends up being locked, then opening hours later. Passenger side lock seem to work fine.