how to avoid the prompt dialoque in crystal report during loading

Question

I am working with the crystal report & I used the command as datasource for viewing data in the report. I used a parameter in that command. I passed value from a combo box to that parameter & it is working fine but when the reports gets load, a prompt dialogue appears which asks for a value to enter whereas i am providing the value to that parameter through combo box. I don't want that prompt to appear. Please help & tell me how can I avoid that prompt from display.

Thanks