Parallelization object &1 is not permitted for mass activity &2

What causes this issue?

You have specified &V1& as the parallelization object. This object is
however not permitted for mass activity &V2&.

System Response

The system rejects the selection of parallelization object &V1&.

How to fix this error?

Use the input help to select a permitted parallelization object.

Procedure for System Administrators

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.