How to add a domain space to your account
If you have a Premium plan account, you can purchase up to 50 domain spaces, additional to your plan’s allowance. To purchase additional domain spaces:
Navigate to Plan and Billing
Go to the Add-ons tab.
Scroll down to Domain space.
Select the amount of additional domain spaces you wish to purchase. Domain slots can be purchased for $4/month each, and each domain space will create a new monthly subscription.
Click Add to cart.
In the purchase summary on the right, click Buy to complete the purchase.
Purchased domain spaces will be shown at the bottom of the page, and can be removed by clicking Remove domain space. If you need to cancel your subscription, be sure to delete the domain and remove the domain space.