RRW3_GET_QUERY_VIEW_DATA RFC Issues

I'm using function module RRW3_GET_QUERY_VIEW_DATA to read data from a BW query. It works fine when I run it in our BW system and provides me the desired results.

When I execute this function module from our ECC system with the same parameters, I see invalid_input error. The issue seems to be with the date range. When I use PERNR alone it works fine. The date range works if I run the FM directly in our BW system though.

The parameters I send include a date range and PERNR which are both defined as select options. If anyone has come across this issue before please provide me pointers on what could go wrong.

Thank You,

Kabir