Create a tenant before you can begin deploying and managing phones.

https://www.youtube.com/watch?v=tbk3zZV-AmQ&list=PLbvpe9Wy6OqEgJvy3gY0qQUDc35ctsyS4&index=2

Tenants are a segment of the business. They can be a site, location, line of business, etc. You can customize this based on your or your customer’s needs to best organize the phones and services. 

...