When the patient has more than one appointment in the future you can send the communication regarding a specific appointment by following the below steps:
Create your communication that you would like to send. The below articles provide guidance on how to create both types of communication templates. You will need to ensure that the upcoming appointment tags are inserted into the communication.
Select the patient that you would like to send the communication to and go to 'Communication'.
Select 'Communicate with XXXX' and using the drop-down list select the specific appointment that you would like to communicate regarding.
Select your template from the drop-down list under the communication that you would like to send. Select the to preview. See below:
Once you have previewed your document simply select the to send the messages.