URL reverts back to default after edit

The “edit” button from WP is gone so there’s just an empty field to type into… so I add my change… and it flips back to what it was…

in my case, i initially installed WP to a subfolder so that my root page could be a standalone Sales page. Now that WP allows this sort of thing, I’d like to pull everything into one system.

So I have an existing page
domain.com/sub/Page1
domain.com/sub/Page2
and posts
domain.com/sub/post-name1
domain.com/sub/post-name2

with the new installation of WP I get
domain.com/Page1
domain.com/Page2
domain.com/post-name1
domain.com/post-name2

It won’t let me insert the /sub/

Any tips appreciated!

Thank you!

https://www.ads-software.com/plugins/custom-permalinks/