Child system &1 is part of another CUA, &2 (CUA &3 not activated)

What causes this issue?

The child system &V1& is already part of the CUA &V2&, which is
administered from the central system &V4&.

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

System Response

The CUA &V3& has not been activated in this child system (&V1&).

How to fix this error?

If you actually want to move the child system &V1& from the CUA &V2& to
the CUA &V3&, first remove it by calling the report RSDELCUA in the old
CUA central system (deletion option: Child Systems).
If this has been caused by an inconsistency, and the child system &V1&
is no longer registered with the old CUA (&V2&), delete the old CUA data
by calling the report RSDELCUA locally in the child system &V1&
(deletion option: Invalid Content in CUA Tables).

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.