How to generate Outbound idoc for Material Reservation

Hi Experts,

I want to send outbound IDoc when a material reservation is created with tcode MB21.

I have been working on this issue and finding the solution in SCN for a week...

I found some messages similar to this but I could not find out the correct way how to do that.

At this moment, I configured BD64/WE20 referring the following topic which seems to be feasible solution but could not find any outbound IDocs created, unfortunately.

Implement ALE_RESERVATION_CREATE

I appreciate if someone can help me how to create outbound IDoc with MB21 or advice some possibility of missing configuration or steps.

Best Regards,

Kenji