404 when logged out but displays OK when logged in

I’ve noticed that a page 404’s when Im not logged in, but loads OK when I log in
So far Ive tried:
– cleared browser history / tried other browsers
– refreshed the permalinks
– flushed it out of the redirection plugin
– changed the page’s URL
– tried accessing the page using its page_id

Wordpress 5.8
Theme: Specular (latest versions)

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