2005 Cadillac Escalade Esv rear hatch door

It is kind of tricky, but you need to remove the trim panel from the door with it closed, access the lock actuator, physically unlock it, and the handle will release it then. I would check signal(power and ground) to the actuator lock solenoid, if it is present the solenoid failed. If you don't have a signal, you could have a faulty control which I think is from the Body Control Module, or wiring. The pass through, where the harness goes from the door to the body, is sometimes the sight of electrical issues.