Terrible call centre service

I have been trying to get hold of Discovery Vitality call centre since last week to cancel my Vitality membership. I have been holding on for several hours in total to no avail. I eventually chose the option to activate Vitality and instantly I got hold of an agent. The agent then tranfers me to the "cancellation" department to which I hold the Line for hours. I asked for a direct Line for cancellations and apparently there is none. I am extremely disgruntled by this service and would like my request to be processed asap.