Cancelation of contract

Something seems to wrong with this company, they are too much *********** and they all seem confused when u talk to them, I took a contract with them I then decided to cancel it as I was mislead by their consultant, my problem is ever since I canceled this contract three month ago they keep sending me sms to say I owe them, I have called them more than 30times to enquire about this cancelation and they keep telling me that someone will call me up to date I am still waiting.... This is far more than poor service.