Tailgate unlocks in reverse

I own a 2001 e39 wagon

I can't open my tailgate or the window without having to do it manually by pulling on the cord inside the hatch.

Everytime i try to open it, it will unlock and move the tailage to where you have to open it manually, but then it will re-engage the actuator and lock again. Also, when i put the car in reverse, it will do the same thing.

I've trying pulling on the tailgate while unlocking it, but it won't disengage fully, and it will re-lock again.

Could this be a wiring issue in the hatch? I wonder this because my rear wiper and washer hasn't worked since owning the car, and i've taken a quick look to see that some wires are either on their way out or already broken in the upper part of the hatch.

thanks