I have 2 company (Company 1 and Company 2) and I want to use inter-company rules. 

Company 1 has service, which it buy from other Country 2. And Company 2 provide this service. 

I set inter-company rules: 

I create service in the Company 1 

When I create sales order and confirm it, Odoo create non-confirmed Purchase order. 

And I try to confirm it, I see User error: There is no vendor associated to the product Услуга 7. Please define a vendor for this product.

Could you please help me, I don't understand how it should work