Declaration nature &1, reason &2, last day worked &3, No. &4 already sent

What causes this issue?

A &V1& type declaration has already been generated in <ZK>Actual File
</>dispatch mode dispatch mode for the non-productive time with reason
&V2& and date of last day worked &V3&, which is why the system will not
generate a new one.
However, if you run the program in <ZK>Test File </>dispatch mode and
without B2A, then the system will generate this declaration again, for
information purposes.

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?

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.