when you are on your profile page, you will see an ‘Edit’ button to the right of ‘About me”. When you click there, you will see the line for your website right above your certifications.
Karin added helpful information or also should try this one for change url address
Click “Settings” under the account menu at the top of the dashboard.
Click the blog you’d like to update on the right side of the page.
Click the pencil icon in the username section.
Adjust your URL as you see fit.