Replace initial permalink with slug

Hi ~ I created a post content using hugo new post/
and the post is accessible from http://localhost:1313/post/bootcamp-start/

However, now I added slug: "techladies-bootcamp" in the post’s front matter.

So now, the post is accessible from both http://localhost:1313/post/bootcamp-start/
and http://localhost:1313/post/techladies-bootcamp/

How can I remove the initial permalink?

This still happens after restarting hugo server?

that’s weird, server was off when I made changes via text editor, and then I started the server.
Now that I stop and restart again, post/bootcamp-start/ is 404 not found