Main information page for students concerning FERPA, tuition, 1098-T, make a payment, payment plans, payment deadlines and refunds. For the open invoice in the Payment column, enter how much of the credit you want to apply.The letter should also state that the debts have been referred to DHA. 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. Remove the credit memo you sent them. When they use the credit (overpayment) apply it to the invoice they are paying. If you get some refund after you paid your credit card bill, that refund amount will be shown as Credit balance in the next statement. Send sample overpayment letter to customer via email, link, or fax. You can also download it, export it or print it out.