Situation:
If you have a booking for multiple properties or multiple dates, any SMS that have been scheduled will be sent for each property and each date.
This means, a guest will receive three SMS, if there are three different properties in the booking.
Resolution:
When creating the template for the SMS, make sure this SMS specific tag, Add property section for SMS, is being added.
It can be found in the list of tag under Booking properties > Booking properties section for automated SMS.

This tag will add the following tags into the template.

Enter your message between the top and the middle tag.
