Check the back of the zipper for any thread or piece of zipper lining that is stuck in the zipper. If you do find a piece of stuck thread or zipper lining gently tug at the thread/lining back and forth to dislodge the fabric from the zipper.
Rub a candle or unscented bar of soap over the zipper's teeth to encourage the zipper to slide more readily and become unstuck.
Dab a bit of liquid dish soap on a cotton swap or your hands and place the soap along the teeth of the zipper where it is stuck.. Work the zipper back and forth till it moves freely.
Lightly dab at the zipper with a wet washcloth to remove the soap or wax, then quickly dry off with a clean rag or paper towels to avoid rusting.
