It is understandable that at times it may be necessary to cancel your appointment. However, as each appointment which you book is specifically reserved for you, the full session fee is still due for the session which you cancel.
If you need to cancel your assessment, please do let me know. Cancelled assessments do not incur any cancellation fees. If you have an assessment appointment booked but do not attend without notifying me, then I may not be able to offer a further assessment appointment.