SSRS Report is Blank

I am trying to change an existing report to get the data from the new stored procedure. The stored procedure is fine and it shows the data correctly.

But when I got to the "Preview" Tab and run the report its blank. I event check with the sql profiler an it does not call the stored procedure at all. The dataSet is correct and I am not sure what am I missing!! Here is the image after I test the report in the preview: