RM5156 | Over-repayments: How to begin to recover an over- repayment
From HM Revenue & Customs · Repayment Claims Manual
When you have decided to recover an over-repayment over £ 100 (RM5148 - RM5152) take the following steps.
Find out whether the payable order has been cashed (RM5160).
Decide how to recover the over-repayment.
If the payable order
has not been cashed see RM5164
has been cashed follow the Inspector’s instructions.