No status change was made for the IDoc to be aggregated &1

What causes this issue?

You want to change the status of the IDoc to be aggregated &V1& to 01
'IDoc Generated'. The IDoc is then not sent via the data exchange
infrastructure when you execute standard report RSEOUT00.
However, the change was not made successfully. If you also use report
RSEOUT00 to send IDocs, an IDoc may be sent twice.

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.