The back door on this vehicle opens from manually or from the button on the dash. However, it very seldom closes smoothly. It jerks and jerks, and not only that it causes on its own without pushing any buttons. It can actually hit you on the head if you’re not careful

 

Time to replace the gas struts, would be my guess. If they haven't been bad for too long you may still have a good lift motor. If you wait too long the lift motor may go bad as well.

 

Buy your replacement hatch struts here. https://www.liftsupportsdepot.com/?c...oaAoOVEALw_wcB