Help with BAPI -> ME22N

Hi,

I need your help.

I try to change the field netpr with the PO BAPI_PO_CHANGE, but I can't because in the trx. ME22N this field is disabled.

This order was create with the PO BAPI_PO_CREATE1, with reference to order request and rfq....

the curious is when I create the order with the trx. ME21N with reference to order request and rfq, this field in the ME22N is enabled....