How to maintain(use) two Delivery related billing types for one sales document type.

Dear Gurus,

Please advice how to maintain two Delivery related billing types for one sales document type.

Business process: Steps

1. Order is created in ECC.
2. Delivery is created without picking, PGI and the delivery number would be distributed to EWM (extended warehouse management) and then Proforma invoice will be created and next picking, packing, PGI will happen.
3. EWM system will trigger billing i.e. Proforma Invoice which should be created by default in ECC, for this ZPPF billing type is created.
4. Later Original invoice should be created by billing type ZFII using billing due list vf04.

Configuration: In VOV8 Sales document type – billing tab – Dlv rel. Billing type - ZPPF(maintained )

So if EWM system triggers billing then by default Proforma billing is generated for them, but when I want to create original billing(ZFII) using same delivery numbers in VF04 it is not displaying and could not able to do original billing by default.

Regards,

KSR