Message SAP WTADDI251 - IDoc cannot be generated by calling BAPI

Diagnosis
You want additionals IDoc generation to be triggered by a BAPI. Thisfollow-up action is not defined foradditionals document &V1&, item
&V2&, schedule line V3& andadditional &V4&.

System Response
No additionals IDoc is generated.

Procedure
INCLUDE ISR_CHECK
You can display detailed data for this document in the additionalsmonitor.