After you have added the Atomic domain names in the Microsoft Admin panel, you need to activate them by adding at least one E1, E3, or E5 licensed user, as well as the Teams Standard Phone license to the newly created base domain.
You can do this by either creating a new temporary user or using an existing user. You need to keep the domain names attached to the user for at least 60 minutes for the activation to be completed. This is a process required by Microsoft and mandatory before proceeding.
Creating a new user
On the Microsoft Admin Panel:
On the left menu from the Microsoft admin page, select Users > Active Users. Click on Add a user. Enter a First name, Last name, Display name and Username. Then select the Atomic domain name that you are activating. Set a Password and click on Next.
Next, in the dropdown list for Select location, select Australia and under Assign user a product license, assign either an E1, E3 or E5 license for the user and click Next.
Under Optional settings, you don’t need to change anything here (as this is just a temporary user and you will be deleting the user after the activation process is completed so that you do not waste a Microsoft license). So you can just go ahead and click Next and Finish adding.
Now comes the waiting part. Microsoft can take anywhere between 30 minutes to 3 hours to activate the domain.