how to get message id from payload

Hello,

Payload contains PO, item and GR details which creates GR for an item.

I have a program which takes input from payload, creates an Idoc with payload data and processed to create GR for PO line item. If PO or PO line item is not present, Idoc is created with error status with says GR is not possible for PO.

In this case, I want the message id linked to that payload so that it can be identified easily and payload data can be corrected.

Thanks,

Spandana