Drag and Drop

I have created an activity which allows users to demonstrate their knowledge of state geography.  I have checked the "Set Correct Answer" panel several time and everything is correct.  However, when I complete the activity nothing happens.  The "On Success" field is set to show "GroupCongrats."  Any ideas what else I should check?  FYI, the activity is set for Infinite Attempts and Auto Submit Correct Answers.