If you were overpaid, you will receive a written notice in the mail. Not OP but received the same letter.Tell them that they have "overpaid" you. Then ask them to ring you for details. We have identified the following overpayment and are in good faith voluntarily refunding all monies collected in error. There has been an error in your favor! Please call 1-800-772-1772 or your local field office and we may be able to process your waiver request quickly over the phone. An "overpayment letter," the gist of which is that an excess amount of benefits has been paid out and so must be returned.