Expand the Users section at the bottom of the default organization you just saved (not from the Setting  menu’s User menu item).
To add a user, click the button.
Since other users have not yet been created, the “admin” user is the only user listed. Select the checkbox beside the “admin” user to select it for this organization, then click Save.
After saving, the organization’s user information becomes available for viewing and the new user you created appears on the list.