(a) In instances where the Corporation is the creditor agency, it shall promptly refund any amounts deducted under the authority of 5 U.S.C. 5514 when:

(1) The debt is waived or otherwise found not to be owed to the United States (unless expressly prohibited by statute or regulations); or

(2) An administrative or judicial order directs the Corporation to make a refund.

(b) Unless required or permitted by law or contract, refunds under this section shall not bear interest.