IDOC CVI_EI_INBOUND_MAIN_M01 gives error Specify at least one number for the business partner

Hello Experts,

We are on S4HANA1909 stack and I wanted to create BP using IDOC CVI_EI_INBOUND_MAIN_M01. Everything works well until BP creation and then in the method CVI_EI_ADAPTER=>DO_START_INBOUND_MAIN I get error message R11 123 "Specify at least one number for the business partner"

From the code I understood that this expect me to pass BP number or GUID, when I am creating IDOC from foreign system I dont have these details.

I dont find any note for this issue, could someone help me in correcting this issue