Entire Connection - Download error

I try download some DDMs from mainframe using DDM task and I have error
“Natural not active on the mainframe - NEXT Prompt not found.”
Could anyone write me what I have to do.

The procedure that is behind the DDM task expects that you have started Natural and that Natural shows the NEXT prompt on the screen.
When you start Natural and enter “mainmenu off”, the NEXT prompt is displayed on the screen.