1. Turn off Free Mode in Admin -> Tools -> Membership Levels.
2. While your there, also turn off "Promo Mode"
3. Drop down a little further on the same page and select Non-Members from the Membership Levels
4. Disable all items except for Articles & Home Page for Non-Members
5. Select "Standard" Membership Level and enable all items for the Standard Member
6. (You've done this already it sounds like, but for the newer members I'll explain) Go to Admin -> Builders -> Navigation Menu Builder and click on each and every menu box. Remove the check mark from the "Guest" Field and click save. You have to do them 1 at a time and this will help to lock the site down fully.
***You can also set an $iflogged at the beginning of each page (right below the page_css... string of code) to further force the issue and to potentially deal with any pages that might have been missed in the Admin Panel.