There are two ways to reschedule or cancel an upcoming appointment.
You can make the changes in the new window and your client will receive a confirmation email and SMS of any changes.
If anywhere through the app you see an appointment card (like on the calendar), you can repeat the same steps after opening the appointment information.
Clients can reschedule or cancel their appointment as long as it agrees with your booking terms. They can go to their confirmation email and click on "Manage my reservations" or log in through your booking website.
Ensure you've reviewed how Jupiter deals with the deposit upon cancellation. Your booking policy in your emails will reflect this. This can be done in your scheduling control settings.