peugeot partner escapade?

My car is due for mot on 24th Jan and have problems with rear twin folding seat. Can't be unfolded because the seatbelt has locked in so strap stops the seat back from being raised,the seat cannot be used.
Would this constitute an MOT failure?


I intend to sort the belt out when we get some decent weather by releasing from its anchor point raising the seat and see if the belt lock on releases. The garage wants to replace the belt at considerable cost. A friend said this folding seat lock in I a common fault which is why you should pull out belt slack before folding the seat and wrap belt around the head reset so you have belt play to raise the seat back.
Many thanks