Seatbelt on passenger side stuck

i have seen this before oddly and i hope this works for you but penatrating oil helped me in the past just to free it up but your car is alot newer so im thinking maybe there is some junk inside the buckle like coffie or what ever

hope this helps you out

How to install a seatbelt in a 2007 GMC envoy in the passenger side

I had the same problem with a 1994 Taurus. Within the front fender was 10 years of pine needles and leaves blocking the drain backing the water up in and over the fire wall and into the front passenger seat floor.
I took a LONG pair of needle nose pliers threw the passenger side door, and was able to remove enough debree. After pulling out out about 5 fist full's of yuck, 1 gallon a water that was stuck some where poured out flushing out the drain. I did the same on the drivers side. After that I had no problems with floods. I hope this helps. If not check your back door weather stripping if you have one. I have heard water leaking behind the passengers seatbelt and onto the floor from under the seat. Got to love Florida's rain season(s)

If both passengers and drivers side retractable belts have stopped moving, then it's likely the controller that's located under the passengers seat has gone bad. If only one side has stopped retracting and moving then that side motor has probably gone bad.

move the seat back to release tension on the belt buckle and then undo it.
Does that help? If not reply.

this is a simple repair many dont know. remove or pull off plastic pillar post cover, seatbelt probably twisted inside. twist it back around so it runs flat and lube slightly with a light lube spray on metal gearing. i had the same problem w mine pk

You may have to replace the seatbelt positioner.
Check with Saturn (or their replacement GM division) to find if the warranty is extended for seatbelts (some manufacturers cover seatbelts forever) 800-553-6000

It could have twisted on recoil and is now stuck. You'd have to remove the interior panel to view that.

On the really bad side, the seat belt pretensioner could have failed or fired and locked the belt in place. If that's the case, I'd have a mechanic replace it since you can trigger an air bag deployment replacing it yourself.

will have to take the side panel off where the belt is located make sure no twists are present. if not pull it hard and see if it retracts, if it still does not retract you may have to replace the unit.
the retraction spring in the unit is broken, or the lock mechanism has failed.