How to default sales area for BP

Dear Experts,

I'm working on a SAP CRM environment that's integrated with SAP IS-U and SD. Whenever a bp (in role contractpartner) is created in IS-U, it's also created as a customer in SD with a default sales area. I want to have to same functionality in CRM. When I create a bp in CRM, it's getting replicated to IS-U and SD, but no sales area is assigned to that bp. We already tried via the organisational model, but this is not working.

Any ideas on how to resolve this?

Thanks!

Regards,

Marjan