This brief but important letter notifies a customer that he or she has overpaid you. It can serve as a very good customer relations letter.You should ask DES to explain the reason for the overpayment. This form is to be used when a student wishes to return a refund check to PCC. The salary overpayment resulted because . We have identified the following overpayment and are in good faith voluntarily refunding all monies collected in error. Find and access your child support money. Collect Child Support.