22 CFR §1306.24

1. (a)MCC will refund promptly to the appropriate individual amounts offset under this part when:
   1. (1)A debt is waived or otherwise found not owing the United States (unless expressly prohibited by statute or regulation); or
   2. (2)MCC is directed by an administrative or judicial order to make a refund.
2. (b)Refunds do not bear interest unless required or permitted by law or contract.