If you try to add/remove questions to a Plan Sponsor while you have a draft report it in the system those changes will not be reflected. You must delete that draft report, select the new questions, and then create a new report before the changes will be reflected.  Follow the instructions below.
 
On the Plan Sponsors tab, you can see whether a report is in draft (it shows the file icon, not the + icon):
 
 
To delete the draft report, go to the Reports page and search for the plan sponsor.  When you see the Draft report for them, click the trash can icon and it will delete the draft.  Then go back in, choose the new questions, and create a new report.