While it is not likely, a student may vote with two clickers in class. iClicker Classic will warn you of if this occurs when you close your session or when you open or close the Gradebook. The student record will need to be updated to remove one of the clicker IDs.
Check with the student to see why two remotes were used and which remote will be used going forward.
Double-click the student's record and highlight the remote ID incorrectly associated with the student. Click Remove to delete the clicker ID.