To reset a Trainee from one course that is part of the Series, select "Users" from the Left Navigation. Next, select the Trainee you’d like to reset and then click on Manage. A panel window from the right will appear.
Now, click the Series tab. In the Series tab, it will list what Series the Trainee is invited to. Click the name of the Series you are looking to reset a specific course.
Click on the Reset button next to the course(s) you need to reset.