Multicolumn Problem with Sub-Report

I created my first sub-report (linked). I wanted it to have 2 columns so I chose Format with Multi-Columns. I am seeing what looks like 2 columns (one in white and one shaded blue) but when I add a data field to the white side, it shows up in the blue side as well. How can I get another column on this report? When I decrease the width of the columns, it adds another column but keeps the same data fields as what is in the first column. Thanks in advance for your help.