Does it unlock properly when you use the door switch??
I suspect your answer will be "no". What you probably have is a bumper problem. More specifically, the door latch assembly and the power lock actuator are connected with a rod with a little rubber bumper at the end. In time, the rubber deteriorates and unlocking becomes a problem. The repair kit is available through GM dealers and is pretty cheap from what I understand. Fortunately I have not had to do this procedure.
Just going from memory, there are 3 screws and several push-in retainers to remove the door panel. One screw is behind the small trim piece that the power mirror switch is located (or would be if not equipped) and the other 2 are behind the white door light. Be careful then prying the lens off cause it's brittle. The push-in retainers are around the perimeter of the door panel. It's helpful to have a "J tool" or similar to pry out without damaging the retainers of the door panel.