Log on to your TherapyPM portal using this link: https://app.therapypms.com/.

Go to Appointment > Calendar View. 

Click on the preferred appointment. An Edit Appointment pop-up will appear. 

Please select the Start Telehealth Appointment option in the appointment and follow the link or instructions I've included.
For example, if you're joining a virtual session with a patient, click the link in the appointment details.