Transfer Cost in F4211

Hi, Please advise on the below

When creating a credit order for a original sale order there was no change in the cost when placing the order. But during ship confirmation seems the cost has bene changed (although PO is not enabled for this) and so the cardex has been updated with different cost for the credit order rather than same as the original sale order.

Upon checking sales ledger for the credit order could see the unit cost and extended cost are same from entry until sales update. But the field "Transfer Cost" has been upated with different cost during ship confirmation. Could you please help to know where this cost would be set? Is there any option to avoid change of this cost during ship confirmation?