Teams Admin: Number Features says "SMS off" how do we turn it on?

 This feature is now part of Teams Premium.

SMS text notifications are currently available in Canada, the United Kingdom, and the United States.

You can control whether SMS text notifications can be sent to external attendees for virtual appointments scheduled by your staff in your organization.

By default, this setting is on, and SMS text notifications are enabled for all Bookings calendars in your organization. Keep in mind that Bookings admins and schedulers can later choose to turn off or turn on SMS notifications on an as-needed basis in scheduled appointment types and scheduled individual appointments.

To configure this setting, go to the Microsoft 365 admin center > Settings > Org settings, and then choose Bookings. Select or clear the Allow Microsoft to send SMS text message notifications check box.