Change Website Name
You organization website name is a subdomain name which you specified when created the organization. (For example:
mycompany in the web address
When you change your site name, the old name will remain valid for three days as an alias. Use this time to update any external links that reference the old address.
If you have any third-party authentication set up, make sure to update callback URLs used in the authentication modules.
On the main menu, click Administration and choose Basics.
Under Site name, click and type in a new name. Enter only the first part of the URL.
Notify organization members of the address change and update all external references.