3433402 - Not Possible to Add a New Party Role to Sales Order

You are not able to add party role to Sales Order.

SAP Cloud for Customer

1. Go to Business Configuration Workcenter.
2. Navigate to Implementation Project.
3. Open Activity List in the current project.
4. Find Sales Orders activity in the list.
5. Open it.
6. Go to Maintain Involved Item Parties section.
7. Go to Party Role Assignment. 
8. Add Row. 
9. You will see that the new line is visible, however, the drop down list is blank for Party Role. 

Only parties with the Z party role codes can be added. 

This is the reason the drop down is empty.

In order to add a new Party Role, please maintain it as a Z-party. 

Party , Involved Party , Sales Order , Account , Custom Party  , KBA , LOD-LE-CQP-CO , Lean Sales Orders , Problem