Payment_Method field in CRM via CRMXIF_ORDER_SAVE_m02

Hi

We are integrating an website to CRM system and creating orders in CRM using Idocs.

We are using CRMXIF_ORDER_SAVE_m02, order is getting created and passed to ECC as well. We have an issue that a field Payment_Method in CRM, need to be filled in for orders created via Idoc.

Any idea, I am not able to find this field