Setting Up Bookings for Virtual Visits

Hey Team, thanks for this wonderful guide!  I'm afraid I'm having an issue in testing the "tab as a Teams app" portion where many of my test users are reporting that it loads up to a blank screen within Teams.  Has anyone else seen an issue like this?  I've had them go to the bookings website and make sure they can open up the "John's Clinic" company that I set up and they are admins in that company so can access the calendar to create new appointments.  Any ideas?