SAP Message V50R054 - Conversion of the identifier &1 from preceding system failed: &2 &3 &4

Diagnosis
When generating a delivery for a preceding document that wanted totransfer information about &V1& to the delivery, the conversion of theidentifier (key) for this information from the preceding system into anidentifier for the supplying system was not successful.
The order item affected is in system &V2& in document &V3& with itemV4.