First of all, here is a video explained how 2-way message and auto message looks like from desktop version:
Turn on Unconfirmed appointment reminder.
“send by One day before” is by default. You can change to other options.
2. Edit message: be sure to include “Reply Y to confirm” from the tag below.(Make sure it is added from the tag below, instead of type in by yourself)
3. Once set up, our system will send a confirmation message to your client "one day before" his/her appointment begins.
If your client reply “Y” in the message, the appointment status on your calendar will automatically change from “Unconfirmed” to “Confirmed”.
4. If some of your clients doesn't do text message, you can also set up "Call reminder" or "Email reminder" in the client profile "Preference" section.
(If you set up "Call reminder", the system will call the client, and ask "Press 1 to confirm, press 2 to cancel")
You can also control if that client doesn't want to receive any reminders.