You do not need to convert archiving session &1

What causes this issue?

When the archiving session &V1& is created from an ILM file conversion,
the composition of files in the new session remains unchanged. The
reason for this is that the rules in Information Retention Manager do
not create a new assignment between the data objects and archive files.

System Response

The status of the previous archiving session is not changed to
"Replaced". The system deletes all the archive files and archiving
management data for the new archiving session because these are copies
of the converted session.

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

Error message extract from SAP system. Copyright SAP SE.