How to *avoid* automatic creation of Peoplesoft Item/Vendor data?

PeopleSoft Enterprise SCM Strategic Sourcing 9.2, Supplier Contracts, SCM Inventory, Purchasing.

In PeopleSoft Strategic Sourcing 9.2, when user awards and posting an event, Peoplesoft creates a new Supplier Contract for the Supplier/Items/Amounts/Min Max Quantities, using the UOM of the event.

We also notice a new line of data is entered in Items > Define Items and Attributes > Define Item > Item Purchase Attributes, for the tab [Item vendor] and [Item vendor UOM].

This new line of data generates UOM and conversion problems in PO and receipts, and users had to delete this line when it appears to avoid Item Vendor UOM different from Item Stock UOM and conversion issues.