Problem With Permalinks

When I first started using WP on https://jamesmarler.com a couple of years ago, I set up my permalinks like this:

%category%/%postname%

The deal is, I have some pages that are straight pages and some that are setup for blog/podcasting. After the most recent update, my one blog page (https://jamesmarler.com/blahg) stopped redirecting to (https://jamesmarler.com/category/blahg) and I got a 404 error alert. However, every other page, except for my home page, showed my blahg category posts. When I remove the custom permalink and return it to default, then everything works fine (as long as I redirect the Blahg page to the correct default permalink).

I would really like for this to be corrected, but, so far, everything I am finding is, to paraphrase, code yourself to death. ?? I love that some people eat, sleep and dream code, but I decided to use WP precisely because it was relatively easy to use without having to do all that intricate work.

PLEASE HELP!!!!