Door locks on it's own

[EdgeyBob]

Hello,

 

I have a 2013 Edge where the driver door occasionally won't lock or unlock.  When locked by the interior button, the door lock stub pops down but then immediately pops up.  So when I think that I have locked the door, I come back to an unlocked door. We  have to climb in the passenger door and open it with the door handle (which works normally).

 

I can manually unlock the door and physically pull the lock to the up position, but the car still won't open from the outside. 

 

Another clue would be that I occasionally I get the "door ajar" indicator and I hit OK, turn off the engine, turn it back on and open/shut the door - and it goes away. 

 

Before I take the panel off, I would like to know if someone had seen this before and hopefully have a simple remedy.