Refusal to cancel service

I requested immediate cancellation on the 7th of February. Supersonic didn't cancel and keep saying to wait the cancellation department to call within 10 days. Nobody calls. When I called them back, I was informed that I had to pay a cancellation fee, but nobody have never ever sent any invoice to pay. They keep charging, charging and refuse to cancel, even when you say you don't want their services. It's such an abusive way of keeping people a very bad service and customer service is just zero, it doesn't exist.