When a sales order or purchase order's "Make Copy" function is used within NetSuite, all the field values present under the eXtendPS-DE subtab are copied to the new record as part of standard NetSuite functionality. 

To prevent this behavior, eXtendPS-DE offers a NetSuite workflow called "eXtendPS-DE Clear PS Fields on Copy [S]". This workflow clears all the copied eXtendPS-DE field values during the sales order or purchase order copy event, enabling new values to be set.

We recommend leaving this workflow in released mode.