404 Error only on page Edit

I have a page on my site titled “Movie Thoughts” that I was in the process of building out. I had pasted raw content from an old blog into the page and published it while in the process of cleaning it up over the last couple of days. Now when I select “Edit” from the page tab of the dashboard (or when I go to the page and click on “Page Edit” I get a 404 error. The page link on the main page is still fine and takes me to the page. I’ve followed all the helps with rebuilding/updating the permalinks (I’ve even deleted the slug in the page Quick Edit and allowed it to rebuild). The only time I get the 404 error is when trying to edit. What is going on?

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