301 redirect after changing permalink structure

I changed the permalink structure on my website:
From: Custom structure (/blog/%year%/%monthnum%/%day%/%postname%/)
To: Post name (/%postname%/)

I was expecting WordPress to automatically create the 301 redirects, but unfortunately that didn’t happen. The weird this is: the old URLs are not generating a 404 error either. Instead, when I visit an old URL, it shows my website’s home page, but the URL is not my website’s home page.
For example, when I visit http://www.mywebsite.com/blog/2022/09/14/post-name, the URL stays the same (meaning, it’s not redirecting me to another URL), but it shows my home page.

Anyway, I’m trying to create the redirects, so that if I visit http://www.mywebsite.com/blog/2022/09/14/post-name it takes me to http://www.mywebsite.com/post-name. Please note: my Blog is BIG, so I can’t redirect each URL one by one. I was hoping that I could create a redirection like the following, using your plugin:

From: http://www.mywebsite.com/blog/%year%/%monthnum%/%day%/%postname%/

To:
http://www.mywebsite.com/%postname%/

Would that work? Is your plugin able to work with those parameters?