Activity & is not assigned to the delta version &

What causes this issue?

You would like to copy planning data for activity &V1& to the delta
version &V2&
The activities have the following meaning:
RKP1 Planning primary costs activity independent
RKP2 Planning activity types and prices
RKP3 Planning activity inputs activity independent
RKP4 Planning statistical key figures
RKP5 Planning revenues
RKP6 Planning primary costs activity dependent
RKP7 Planning activity inputs activity dependent
RKPW Planning secondary order costs activity independent
RKPX Planning secondary order costs activity dependent
Activity &V1& is not, however, defined for the delta version &V2& in
controlling area &V3&.

System Response

Activity &V1& may not be copied.

How to fix this error?

Exclude the activity &V1& from copying.
OR
Assign the activity &V1& to the delta version &V2& in controlling area
&V3&.
-> Version maintenance <DS:TRAN.OKEV>Execute function</>
OR
Use another version as the copy destination.

Error message extract from SAP system. Copyright SAP SE.