Hi,
I am not sure how your system allowing to change value for deleted item for a PO but as item set for deletion flag - No issue, the condition type is in INACTIVE status for that PO with deleted item.
As your purchase order item set deletion flag, the value in the item related to Net price field will be there, also at the same time - the value will be available in Item Detail of PO for that item in condition type but the condition type is in INACTIVE status.
As in your case- you have two items, one item is set for deletion flag and for other item, the value will be there and can find that only one item value in PO Header Level in Status TAB
Regards,
Biju K