Hey Bob, this is a new one! I haven't had this problem, or heard of it before. But, one thing it could be is the bracket on the door. It may have bent outward, over time, allowing the pressure from the latch to let it creep up. You might try tapping the bracket in, gently, with a hammer to get it more vertical. Just a thought, and is what I would suspect first. Others may have a better idea!