Return Order billing

Dear Sap Guru's , I have peculiar problem...

I have done the return order configs.

My return order got delivered and PGI

But when I bill the delivery it billing is not generated it say sales organization is not defined.

The error message.

0084000000 000000 Sales organization is not defined

Client 100

Group Number

Sales Document Number 0084000000

Item Number of the SD Document 000000

Schedule Line Number 0009

Counter in Control Tables 00

Message Identification VF

System Message Number 009

Output Type E

Message Variable 01

Message Variable 02

Message Variable 03

Message Variable 04

Group Type F

posted by,

Amlan Sarkar