I'm not 100% sure what you mean mate, I'm guessing your seatbelts are not pulling out?
If so you could remove the rear side panel trims and remove them to see it anything is jamming them or if they can be pulled out on the bench. They don't have explosive pre-tensioners, just a ball bearing mechanism as far as I can see. If that isn't sitting level you might find the belt will not release.
Jay