Business partner &1 is already assigned in role &2

What causes this issue?

The partner is already assigned to the Real Estate object from &V3& to
&V4&.

System Response

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

How to fix this error?

Delete the partner assignment or change the assignment periods.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.