New page missing

My browser (IE6) crashed as I tried to add a new page using the current version of WP. It added the link to the Contents list but when you click on it you get Page not found. Check for yourself, the site is https://www.robinfaichney.org/ and the page is The Book. How should I clean things up? (It would be nice to retrieve the contents but I don’t expect that will be possible.)

R