Message SAP BORGR656 - Existing inbound delivery &1 contains items with different pick-up list

Diagnosis
If you want to change inbound deliveries using an IDoc, all items ofthe inbound delivery must refer to the same pick-up list. The inbounddelivery must not contain items which do no refer to a pick-up list. Anexception are packaging material items and subitems which have beengenerated automatically. These conditions do not apply for inbounddelivery &V1&.

System Response
The system does not change the inbound deliveries.

Procedure
Check inbound delivery &V1&, item &V2&.