Menu Editor not reflecting changes on live site

I am trying to edit my menu so that it has a dropdown item, and so that it is in a particular order. However, the menu never changes on the live site, and always appears as the “page list” option, with no dropdowns or particular order. The problem does not change when using different themes. And when replicating it on a wordpress.com website with the same content, the problem persists, in addition to not being able to access the menu editor from “site editor”. The theme currently being used is “Zoology”.
The linked website is a wordpress.com version of a duplicate site which has the same problems.

It may be a problem with the editor, although I doubt it as I am very new to wordpress.org. Any ideas what the issue may be?

The page I need help with: [log in to see the link]