“I made a mistake on a Facebook page name and now the URL is all screwed up. I typed in the wrong letters and didn’t noticed it until afterwards. Now I would like to set the correct URL. How can I change the page URL?”
Unfortunately the answer is No. By clicking the ‘Confirm’ button you have claimed that specific URL (username) and there is no way to change, transfer or edit the page. The only thing you can do is create a new page with the correct URL and start over.