You already have a subscription when I actually do not


I have a logged out browser trying to buy a membership on the site. When I select Student Membership, it goes to a screen that says I already have that subscription and that I can choose to purchase a different one. I did not purchase the Student Membership yet, it just gave it to me for free.

I believe this is related to the Use Subscription for registered but no access level setting perhaps? It is currently set to "None". Please advise, we want nonregistered visitors to be able to buy either student membership, or the two other memberships there. FYI we have two access levels, Members and Visitors, and three subscription plans.

Thanks and regards,