Poorest Internet ever, refusing to cancel my subscription

If there was minus 1 star, I would give that. I have called Rain several times to have my subscription cancelled from the 1st of June and to this day I have not received any confirmation. Everytime I call I am promised that someone will call me back but nothing. I am being billed for a service I am not even using it is frustrating! I have complained about lack of internet that I have been experiencing and Rain does not seem to bother, as long as they bill you each month. I want this cancelled immediately because it is a ripoff and I will never recommend it to anyone ever!