Trouble With URL

Hi,

I used /%postname% as the custom URL structure in the permalinks settings, so it would make my dynamic URL’s more friendly. It’s worked well, but the very first post I created I called it “facebook test post”, it was just random post I made when I was playing around with a few things. Now, even though it’s been renamed to something different, the URL is showing …com/facebook-test-post instead of /who-unfriended-me-on-facebook

How can I resolve this?

Thanks,

Jason