Sales Order No profitability segment!! Account assignment error!!!

Dear Experts

We are running an MTO(make to order) scenario!

First we create an contract in the system!Then we create sales order

with reference to this contract!

And when the sales order is sent to the planning department! They use

TCODE:CO08 create production order with reference to the sales order!

But we get an error message as follows:

Account assignment cannot be carried out because of different origin no.

Message no. V1134

Diagnosis

The sales document to which you want to refer is based on sales document 41033737 and item 000010.

Therefore, the settlement and possibly inventory management are carried out using the number of the

preceding document.

ut when I entered the the contract in Co08 and then I am able to create

the production order.

And when I back to see the detail in the sales order ,I find there is no

value in the account assignment to the profitability segment!!

Why the sales order have no profitability segment??*

Why we can not create production order with reference to sales order??

It seems there are one problem!

Thanks for any reply!!