2007 Milan door lock problem
 

The doors will not lock every time I use the key fob. Sometimes if I shut the door hard, it will then work. Other times I can shut the door a thousand times and it will not work. Of course at other times, it works just fine and locks with the first push of the button. It always unlocks without any problem. Using the inside lock button always works. There are no buttons on the door frame to clean and I have been told there are sensors in the door handle. Anyone have any ideas, I give up.