How do I hide list titles based on prompt values on a sectional report

[paula919]

I created a sectional report in report studio by sectioning two of the columns from the list. I am using both the sections and another column from the list as prompts. But the problem is that although I select only a few values from the prompt page, the other values also get displayed on the report. I tried to solve this by editing the value as "if [Group Name] in ?Group Name? then [Group Name] else NULL". This solved my problem partially by eliminating the group name sectional header, but I still see the list headers on the report. Can someone give me an idea as to how to go about this. Thanks in advance.