Dos this happen when your FOB is nowhere near the vehicle, or does it happen when it is near the vehicle?
Mine opens sometimes, when I am around the back of the vehicle and get too close to the bumper. I checked the sensors in the back but found they are just too sensitive.
So sometimes while loading and unloading, if my feet are near the sensor, the lid will shut on me. Annoying, but I don't want to totally turn off the liftgate function.
I have yet to find a work around.