Seatbelt issues-91 Infiniti G20

Hello.

Im a new driver and just bought myself the Luxury of the Nissan car line an Infiniti.

Make: Infiniti

Model: G20

Year: 1991

Milege: One hundred and twenty thousand

Engine: 2.0 L

now heres the issue.
I happen to like power seatbelts and in my Infiniti it happens to have them. They have worked fine since ive bought the car but all of a sudden during driving it started tighting on me.I thought my car was trying to strangle and kill me. Well I unhooked the drivers side auto seatbelt with the emergence latch and it was fine. When I when to open the door a thick black wire covered in somekind of oily substance has popped out of the door jam where the seatbelt is and the power seatbelt will no longer slide back and forth. It now stays in the open positionwitht the wire hanging down. Ive tried to push it back in but that doesent help at all thier is to much leway I know it is not broken because you can still hear the motor trying to pull it back in
now the passenger side works fine. Can you help me or direct me to a online domain where I can learn how to fix this issue. Im handy but I dont want to break the car. Its my first car. Mista2dop3@gmail. Com