The bank told him that he couldn't get the money, and you didn't know why you wanted to return it. Usually, if the stated purpose is wrong, there is no reason to return the goods. It should still be accounted for, and it is likely that the remittance information is wrong, such as the payee's name and account number.
3. If the bank says it wants to pay back, it means that it has not been recorded or has been written off after being recorded.