Ì did a test live subscription at that same plan that you mention, and was able to set it up successfully, and recurring payments set at the correct $6.99. I sent you the details privately (screenshots, etc).
I tried to see the sales page you created, but the Membership Options Page is still the “be back soon” one. Could you show me the page you created so I review it and see if I notice something that may be causing the problem you’re having? Give me a link to it, or at least the ID or name, so I go to its editor.
I look forward to your update.