Site Role is Defaulting

Hello,
I am trying to make certain courses available only to site “Participants” but my WordPress has been defaulting all new registrations to participant.

I thought I could maybe get around this glitch by also adding each member to your plug in under members and changing what subscription they are subscribed to. I then added the short code to the course to restrict users that weren’t subscribed to that subscription.

When I created my dummy account, I wasn’t a paid subscription and yet I could still access the course. I am not sure if it’s because currently the course is free? I can’t seem to get this to work