How to cancel and charge client for their missed appointment

[tlcfancy]

I have a client who has booked an appointment through the appointment app. She just notified me regarding rescheduling her appointment and it's past the allotted time frame. I am looking for the option to charge the client for her service but I don't see that option even thought the client has held her credit card for online booking and understands my posted policy regarding cancellation. Will an option to charge her not appear until her actual booked appointment time has passed? 
Please advice.

[RHatch]

You can set up a fee for missed appointments and have it autocharge.  Here is the help page on that.

[Helen]

@tlcfancy I just wanted to add here that if your customer hasn't canceled the appointment you can do so from your booking calendar. Click on the appointment in your calendar to see the details, and click Cancel Appointment at the top of the screen.

From there you'll see the option to enforce your cancellation policy and charge your customer's card.

Thanks again for your help @RHatch!