Hello Anderson,
I am not clear with your statement "The task is not related to the posting change" Can you please describe more?
Anyway, let's assume your ERP to EWM QM settings is correct and you trigger the posting change from EWM based on QM interface settings as mentioned by Juergen.
My question is - when you check the PPF tab of your posting change in /SCWM/IM_PC:
1) what is the overall status of the document - you say it is "Not Started"?
2) do you see the "Send ERP Delivery Messages" PPF action?
Thank you.
Petr