Door strikers may be out of adjustment. A good trick is to loosen them just a hair, not even enough to move them by hand, and then close the door on them a couple of times and tighten them up in their new location. This is a trick I use on sliding doors, don't know if it applies to your situation but figured I could try to help out. Good Luck. And don't forget to lube the heck out of the latches (or maybe replace them.