My rear seat back folds down on lifting the seat lever, but won't roll up. Is there a cable release mechanism the should unlatch the rear two attach points?
If you have a 2 door, once you pull the handle to fold the back down, the bottom of the seat should be unlatched and the whole seat should fold up against the front seats.
Folding the rear seat should release the rear attach points. Check to see if something got jammed in there or if the front attach points aren't connected properly.
Seen lots of issues with the cable that detects fold that releases the lower latches. decently common, can sometimes be fixed by resetting the cable, sometimes needs one or both sides, even some needing the cable that goes to the lever.