This is the result of a (kinda stupid) new change by Wix that now keeps the slug static… which completely kills the whole point of 'dynamic’.
While this might be good for SEO purposes, it does not fit all use cases, especially ones where the links need to be changed dynamically based on the content in the CMS.
I personally am not a big fan of this update either, and I believe @noahlovell has taken up this issue with the Wix team already. It would be nice to have a boolean atleast, which could be toggled to enable / disable slugs updating dynamically, however until that happens, the only possible workaround available for this right now is to configure a data hook using Velo code.