Lessons must be cancelled at least 24 hours before the lesson starts. If the lesson is canceled within this timeframe, the used credit will be refunded to your account automatically.
Canceling a scheduled lesson
In the main portal view, under upcoming classes, click on the cancel button for the lesson you wish to cancel.
Rescheduling a lesson
To reschedule a canceled lesson, follow the normal prodedure to book a new lesson with your teacher, as described in this article