"trying to change an appointment"

I was trying to change an appointment for my son at the Children's OPD. called the number and spent 30 minutes being passed between departments. I was then cut off and when calling back was told by an automated message that the imperial booking system cannot cope with the volume of calls. my request is not a difficult one, and at the moment I still have not been able to change the appointment. why can't imperial do basic administration tasks?