Templates Not Working Help!

So I have several custom templates for pages that have been working fine. I went to create a new one today as always and uploading it via ftp. It shows up fine on the Pages list of available templates but when applied does not work on the site. If I set the parent of this page to a different page it then magically works so I think the code for the php file is fine, but I don’t want this page to have a parent.

What the Hell. I’m getting really frustrated, anyone with any ideas? The website in question is https://www.najulda.com and the page that won’t work is https://www.najulda.com/humoso. It should look pretty much just like https://www.najulda.com/creature.

Any help would be really really appreciated.