Air Bag light comes on when I start the car and it won,t go off. on 2003 Jeep Liberty

Had Mec. look at it and they said it was in the driver side seat belt retractor, what's up with that? It seems to come and go? When they tore apart the seat belt retractor on the drivers side it went off for about 6 to 8 months.

Asked by for the 2003 Jeep Liberty