The back hatch door will not unlock

Try your fob?

Inside release button?

Hit unlock several times?

Key will not open from outside?

If all these fail, someone will have to remove the panel inside the vehicle and manually open to inspect for failure

Roy

If you hear the motor o working then you'll have to take panel off and see if there is broken cable or clip to open the liftgate it may be one of your switches not sending a signal to gem module or gem module not sending back to release latch which wold require scanning which any pro can do