Hopefully this helps someone - I’ve had the same issue for a week or so - my freezer door kept popping open every time I shut the refrigerator door. This is a Whirlpool side-by-side. There is a screw at the base of the freezer door (bottom left hand side) that was loose. When the door opens and shuts, it raises and lowers, and when it is shut, it’s at its lowest point. This screw was so loose that it was raised up high enough that the freezer door rested on it and the screw prevented it from lowering completely - this was just enough pressure to make the door pop open with a change in pressure or a slight jar. Hopefully this helps someone else - it ended several days of frustration for me.