3778331 - Cannot Update Custom Field on Inbound Delivery via API After Distribution to Warehouse Management in SAP S/4HANA Cloud Public Edition.

Updating a custom field on an Inbound Delivery via API_INBOUND_DELIVERY_SRV fails with the following error:
"VLA 302 – Unable to update Inbound Delivery since already distributed to dec.system"

The same update succeeds when performed manually through the Fiori app (e.g., VL33N).
The update also succeeds via the API when the Inbound Delivery has not yet been distributed to the decentralized Warehouse Management system.

SAP S/4HANA Cloud Public Edition

• Create an Inbound Delivery and allow it to be distributed to the decentralized Warehouse Management system.
• Send a PATCH request via API_INBOUND_DELIVERY_SRV to update a Custom Field (e.g., YY1_<FieldName>) on the distributed Inbound Delivery.
• The API returns the error "VLA 302 – Unable to update Inbound Delivery since already distributed to dec.system"
• Open the same Inbound Delivery in the Fiori app (VL33N) → Header Details → Custom Fields tab, and update the field manually. The update succeeds.

Once an Inbound Delivery is distributed to a decentralized Warehouse Management system, the Warehouse Management system becomes the leading system for that Inbound Delivery. To preserve data consistency, the API locks the Inbound Delivery and rejects all updates.

The Fiori app uses a different, more flexible path that allows updates to Custom Fields not relevant to Warehouse Management — this flexibility is not available in the public API.

This is standard, expected system behavior by design.

Recommended workaround:

• Update the Custom Field on the Inbound Delivery before it is distributed to the decentralized Warehouse Management system.

For a long-term change:

• Submit an enhancement request via influence.sap.com to request alignment between the Fiori app and the API for Custom Field updates on distributed Inbound Deliveries.

API_INBOUND_DELIVERY_SRV; VLA 302; VLA/302; LE_SHP_ODATA_API_OD/026; LE-SHP-API; Inbound Delivery; Custom Field; Decentralized WM; Decentralized EWM; Distributed Delivery , KBA , LE-SHP-API-2CL , Interfaces for Delivery Documents (API) (Public Cloud) , Problem