bapi_po_create1

Dear all

I m using bapi_po_create1 to create PO , it is a combination of service and material .. for material im not passing NETPR ,but PBXX condtion type with value im passing ,, now ths bapi thro's error ''net price must be greate than zero'' if i enter NETPR there is no error but net price should the value of PBXX.

How to rectify this.

Thank u