Poor cancelation feedback.

I have been trying to cancel my wifi for 3 months. I have sent 3 emails already but the service is poor. I was told by the billing department that I would be refunded for the month that has been deducted after my cancelation but that has not happened. I have to say I am very disappointed because this is a simple thing to do. A request has been lodged in terms of my request but it has been several months and empty promises.