Down payment- Making closing invoice delivery releated-S/4Hana Cloud

Hello,

Now currently we are using down-payment process for our sales orders. And we are using the CBAO item category. After we take down-payment we need to create invoices with respect to per deliveries. For example customer ordered 5 piece and at the beginning, we need to deliver 3 of this material. we can create the delivery document for just three of them but we can not create a billing document with respect to these 3 pieces delivery.

Most probably because CBAO item is not delivery releated we can not create it.How we can create bills per delivery with the down payment process? Thank you,