Edit preview looks fine, while the normal preview is completely messed up, why does this happen?

My site looks absolutely fine in the editor, but whenever I go to see it in the preview it's completely messed up. Why does this happen?

Am I doing something wrong or is this a bug?
For reference the section that I'm using is one of the premade sections that squarespace gives you. 

The password to my site is: website

Can you share your website URL and this page? Site wide password too if this isn't live, thanks!