The driver's seat belt no longer functions. the seat belt can not be buckled. when the metal belt tongue is inserted into the buckle, it will not latch. the latch seems to be jammed. our family owns four similar model ford super duties and this problem has occurred on two other of the trucks' seat belts. this is a serious safely issue and appears to be a vehicle defect. we have notified ford motor company and they said no recall exists so were not willing to assist in correcting the issue. the needs to be addressed immediately. *tr