Deleted category slug page still working

Hi,

I deleted an old category with the slug ‘smoker-reviews’ and created a new one with the slug ‘reviews’ instead. The new one is working just fine but if you manually type in the old slug, that page is still live creating duplicate content on Google. How do I delete the old slug page?

This is the one I want to show – https://www.burningbrisket.com/category/reviews/pizza-oven-reviews/

This one is also still showing but needs to be gone from my website – https://www.burningbrisket.com/category/smoker-reviews/pizza-oven-reviews/

Note – the old, should be deleted slug ‘smoker-reviews’ only still works for categories with this as a parent category. The root page https://www.burningbrisket.com/category/reviews/ works and is as it should be. https://www.burningbrisket.com/category/smoker-reviews/ lands on 404 which is correct as well. So, the issue looks like it’s only pertaining to any sub-categories of the old slug.

I’ve checked that the old category page is definitely deleted, purged caches, deactivated some plugins to see if something else was affecting it, deleted the new category and recreated it, manually updated the parent category on sub-categories and none has worked so far.

I know I can just create a redirect from the unwanted, old slug URL to the new one but I’d like to remove the page so that it’s no longer on my site.

Any help would be much appreciated!

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