After your initial username change you are just allowed to alter it when, according to the rules and standards of Facebook.
How To Find My Facebook Url
Get a New URL.
Action. 1 Visit to Facebook.
Action. 2 Clear the URL bar, and enter "www.facebook.com/username." Select from the list of readily available names, or examine package next to the empty field to go into a customized username.
Action. 3 Click the "Inspect Accessibility" button, and click the "Verify" button to finish the process.
Change Your Existing URL.
Action. 1 Click the "Settings" button at the top of the Facebook website.
Action. 2 Click the "Modification" link beside the "Username" section. Highlight your existing user name and press the "Delete" or
"Backspace" button to remove the existing name, and enter a brand-new username.
Action. 3 Click the "Inspect Schedule" button, and click "Validate" to complete the switch How To Find My Facebook Url.