To activate SMS reminders, you must go to the following section of your platform and check the box:
This way, from that moment on when a user registers, he/she can have an option where he/she accepts to receive notifications by sms.
If you already have registered customers and you want to include the option for those customers to also receive sms, you can write us to support@calendarspots.com so we can activate them manually in your platform.