Child theme only loads on home page

I scoured the code in the parent theme for any clues, I found none. The one clue I found was that the 404 page worked as expected, which tipped me off that something was up with the page-templates.

To resolve the issue, I opened a post, changed the page template to another one (for example “contact form”), updated, then changed it back.

I have no idea why that worked, it appears to be a wordpress bug.