Partial billed for return order

Dear Experts,

I would like to config SAP to suit the following return flow

1. Create return order

2. Create return delivery (our customer will return both good stocks and damage stocks)

3. Create credit for return for those good stocks only.

I have set billing relevance of item category REN to K - Delivery related invoices for partial quantity. So when 10 PC are received (in which 8 PC are in good condition), we can create credit for return with the 8 good PC only.

But my question is the status of return delivery remains "being processed".

Is there any way to make it as completed? Or on the other hand, once a credit for return is created, the return delivery will be marked as completed? Thanks.