I have set up the Billing Type for sales relative and Delivery relative in sales order type.
For example, I setup the ZF2 billing type for delivery-relative billing type in sales order type ZOR.
But it's strange taht no matter what billing type I setup, the system always use F3 billing type.
If I delete the F3 billing type, even though I don't use it in any sales order type.
The system always show "F3 billing type is not defined".
Could anyone can tell me where is the system set F3 for default billing type?