camt.087
The ISO 20022 message asking a bank further down the chain to correct a payment that has already been sent.
Its full name is RequestToModifyPayment, and it belongs to the exceptions and investigations family. It is used when something in a cross-border payment went wrong but the money shouldn't come back: the beneficiary's name is misspelled, the account number has a digit too many, or the remittance reference is missing. The receiving bank replies with a camt.029 saying whether the change was made, refused or is still being looked into.
The same job used to be done in free text in Swift's MT n95 messages, leaving an operator on the other side to work out what the sender meant. With structured fields, the case can be matched to the right payment automatically. It doesn't change the fact that the most common reason for an amendment request is still that somebody mistyped the original.