Membership Premium- Users being redirected to Protected Page

My new "Subscribers" are being redirected back to the "Protected Page" after finalizing their payment.

I'm currently in PayPal Sandbox mode.

They should end up at a "Podcast" page.

I've added that page to the positive rules for that level of membership, and in the negative rules for the visitor level. The latter is clearly working, but it seems the site doesn't view them yet as a "Subscriber".

Any ideas...