The "Domain must be unique" error occurs because each customer account in our system must have a unique domain. When creating a new customer, you need to enter a domain that isn't already associated with another account.

To resolve this, make sure you're entering a unique domain for the new customer.

You may need to check under the Prospects page under uService if an account exists there with that domain.

You can upgrade your prospect to a customer account in the Prospects tab by selecting the option "Skip to Upgrade" in the action items menu for that prospect.

If you need to add users with different domains to the same account, you can take the following steps:
1. Enter a unique domain initially.
2. Create the customer account.
3. Then turn off the Domain Lock setting for that customer.