"Unable to cancel my appointment"

I need to cancel my appointment and have tried numerous times to get through to the number provided for Basildon hospital and the dermatology department with no answer.   I did not want to just not turn up as the appointment may be used for someone else, but how am I supposed to cancel the appointment if no-one will answer the phone.   There needs to be a better method in place for patients to manage their appointments, such as an online management system, as there seems to be many patients having the same problem as myself.   I have to work and do not have the time to sit listening to a phone constantly ringing out, so unfortunately I will not be turning up for the appointment and am unable to advise the hospital of this.   I will not be ringing PALS about this.   I have wasted enough of my time.