Turn over the zipper area to make sure the fabric isn't caught in the zipper teeth. If so, pull the zipper slowly while having another person pull lightly on the fabric at the same time. If not, lubricate the plastic zipper teeth with dry bar soap. Sometimes just a little movement is enough to free the zipper.
I looked into our system to see your record on 11/12/18 and did not see your name as a customer. In general, use paraffin wax to lubricate a stuck zipper. Another suggestion is to use a tooth brush with vinegar to remove any dirt, grime, or salt residue. Thank you for your question.
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