BAPI_SALESORDER_CHANGE message V1045 - Enter the document #

Hi,

I am trying to call the FM BAPI_SALESORDER_CHANGE in my SAP ECC RFC. I am giving the sales order# to t'he FM BAPI_SALESORDER_CHANGE but it still

gets back with the error message V1045 - Enter the document number'.

I applied the following note:

- 1232196 - Inexplicable error in BAPI

- 393728 - SD sales document cannot be read

None of them worked.

Thanks in advance,

Karuna