Due to a limitation of the Sierra API, each User must have a Sierra Agent Profile, as well as a Lead assigned to them in Sierra, before they can be enabled in the Manage Users page of the CBX.
On the Sierra Interactive home page click Users in the navigation bar and select Users from the dropdown menu:
Next, click the + icon in the Agent Profile column row for a given User:
Click Save and Exit:
Finally, refresh your CBX Manage Users page to see the added User:
Note: a Lead must be assigned to an Agent in Sierra before the Agent will appear on the Manage Users page of your CBX.