The Department may seek repayment of benefits from an individual who received benefits under this title if: the benefits were paid erroneously or as a result of willful misrepresentation by the individual; or a claim for benefits under this title is rejected after the benefits were paid. The Secretary may waive in whole or in part the repayment of benefits under subsection (a) of this section if: the error in payment was not due to any false statement, nondisclosure of material fact, or misrepresentation by a covered individual; or the repayment would be against equity and good conscience or administrative efficiency.