Membership registration is successful, but new user is not assigned to any level

I can walk through the process, from signup through Paypal sandbox and return back to the site, but the protected content still cannot be accessed by the "user".

In the Membership area I can see the user has been signed up but not to any level,even though they signed up under "Plan A". When I assign them to a level everything works fine.

Any assistance you can offer would be a big help.