Create Return Order via Fucntional module

Hi all,

I am trying to create a return order with refernce to invoice via fucntional module SD_SALESDOCUMENT_CREATE

In SALES_HEADER_IN, I am giving REF_DOC - Invoice number, REFDOC_CAT - M

In SALES_HEADER_INX , I am putting X mark for the above fields

I am Passing necessary details with material.I see the return order is created succesfully, but the invoice number is not updated in Accounting tab - Reference fields - Header.

Please anyone help me if the values what I have passed is correct or not to create the return order via Functional module

regard

Mano