Cannot updateIB owner's bill-to address using update_item_instance.

Good morning.  I am trying to update these things in an IB record, by calling the API, csi_item_instance_pub.update_item_instance.

• csi_item_instances.attribute10
• csi_item_instances.attribute13
• csi_ip_accounts.bill_to_address

The API call returns SUCCESS.  It updates the 2 attributes in csi_item_instances, but does not update the bill_to_address in csi_ip_accounts.  Again, there is no error, nor any error message -- it returns SUCCESS. 

I''m wondering if I'm populating the correct records/tables to pass to the API.  Here are the records I'm populatiing:

         l_instance_rec.instance_id := l_instance_id;