You can get a seat frame at an auto parts recycler (junkyard) if you don't want to buy a new one. It could be a safety issue in a crash or it could break injuring someone if not repaired. You could take it to an upholstery shop for an estimate.
My car just went of warrenty. The dealer changed the right bottom front seat about 18 months ago. Did not say what the problem was as the warning light came on. I now have 52,000 mile on it now and the light is back on. This car has never been damaged. Is this a recall problem?