2011 transit connect door won't lock

My ford transit connect 2011 is not able to lock regularly. When I bought it used it locked fine. Now the doors lock and then immediately unlock, as if they have sensed that one of the doors are open. The open door light is on. It has been getting worse. Sometimes if you keep trying to close all the doors, especially drivers door, it will lock. This has also happened with teh passenger door or other doors, it just seems most frequent with the driver door. It can take over 50-100 tries to lock it. This is very bad because I live in a city. I have paid over $600 to replace the driver side actuator and remove the after-market alarm, with no luck. Would love some help/ideas.