For country &1, payment reference &2 is not correct

What causes this issue?

There is a check routine defined in the system for country &V1&. When
this routine was used for country &V2&, it found an error.
The error may be the result of an incorrect check digit. Other causes
may be an incorrect field length (the number is too great, or the value
too short) or the use of a character which is not permitted (an
alphanumeric value in a numeric field, for example).

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?

Check whether the number was transferred correctly from the original
document.

Error message extract from SAP system. Copyright SAP SE.