Only root roles can be unlinked from a portal role

What causes this issue?

Role &V1& shall be unlinked from a portal role, but it has a parent
role. Only root roles can be unlinked from a portal role.
All child roles will then automatically also be unlinked.

System Response

The function was not executed.

How to fix this error?

Execute the function on the root role that should be unlinked.

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.