Bank account management has no entry with bank key & and account &

What causes this issue?

Bank account management has no entry with bank key &V1& and account
number &V2&.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Please maintain a bank key in bank account management.
IF &DEVICE& = 'SCREEN'
<DS><DS:TRAN.FI12>Execute function</></>
ENDIF
If the currency and/or a branch number is encoded in the account number,
you have to maintain the account number in the "Alternative Account
Number? field.
If the house bank accounts were maintained correctly, it is probable
that a file with errors was imported. An indicator for this is if the
error message does not contain a bank key or an account number.

Error message extract from SAP system. Copyright SAP SE.