lying to retain clients

About a year ago my contract with autopage ended and a lady from the call centre who's name I do not recall phoned me for an upgrade. I advised her that I did not want to upgrade I want to cancel the contract, I then asked her if I cancel the contract do I lose my number and she said yes. So I said ok what can I do to keep my number as I didn't want to lose it. She then told me about a deal for R50 just to keep my cellphone on. Which I agreed to. Then I notice im still being charged R99 a month which I left. Then I call in to tell them I dont want the number anymore and the told me I need to 13 months payments upfront to end the contract and im saying to them what will I be paying for as i already paid up my device. They then advised me of a new contract that I entered into and thats the cancellations policy. I really feel I have been unfairly dealt with by altech autopage and been **** to I wish I can get hold of my telephonic discussion with that lady coz I am not paying them another R1. All they did for the past year is load the same old phone with airtime every month. Now I must pay them over R1000 to stop sending me airtime. Thats bull.