ABAP RESTful Programming - Unmanaged with Draft Value Help with Binding not working

[Andre_Fischer]

I created an app using Unmanaged with Draft(early numbering). I have a Header and an Item level.

At the Item level I have some fields with Value Help which have additional bindings related to the fields defined at the header level. When I am creating a new Iteam with Draft the fields derived from the header are initial. If I can put default value to these binding fields during the creation of the item I would solve my issue (I tried in method earlynumbering_cba_items)

Also I have to set some default values for some of these fields based on the header level fields.

[Andre_Fischer]

What is the version of the underlying ABAP Platform that you are using ? (SAP BTP ABAP Environment, S/4HANA 2022, 2021, ...) ?

Which OData protocol is used by the service binding ?

Unfortunately setting default values for value helps greatly depends on these facts.

[grigore_turcan]

The version is S/4HANA 2022 on premise. OData V2.

[grigore_turcan]

Yes, the views are exposed, and everything works if I read from original Database Table. But when I am creating a new line item in draft the values are not read from the header: