My 2001 Buick Park Avenue has a problem with the seat belt on the driver's side. At various times the belt cannot be pulled out of the slot in the left side below the seat. Pulling and pushing doesn't release it. Then, for no known reason, it will release so the belt can then be connected and secure the driver. At other times it freely comes out of the slot. It retracts normally when the belt is disconnected at the buckle.
The seat belt is in excellent condition, no wear and tear is observed. Can anyone suggest how the problem can be resolved?