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.For the open invoice in the Payment column, enter how much of the credit you want to apply. The salary overpayment resulted because . If you were overpaid, you will receive a written notice in the mail. The District Clerk's Office accepts the following forms of Payment: 1. Cash Bring your cash payments to the Civil Courthouse. We're making it easier for your clients to receive, complete, and submit important documents using their personal my Social Security account.