All cancellations must be processed through the SIF Health booking system, either cancelled by the client their side, or by you.
If you are using Crezco, then you are in complete control of the refunds. This relies on your side to refund the client the payment if you so wish (Crezco payments are immediate into your bank account).
If the cancellation is processed through the SIF Health calendar then that time slot will free up to enable another booking. Likewise, if a client cancels their end, then this will open up the slot in your diary again for another booking.