Bound to contract for life

On the 20/04/2015 I app**** for wifi and I stated that I want it permanently fixed to my house and when it was delivered on Tuesday the 28th April it was mobile wifi. I called mweb on the 29th to let them know that it would not suite my needs as we already have a mobile wifi and we are unhappy with it, I was then advised by a lady only known to me as Haggi that I needed an ADSL line, which I told her to go ahead and get it for me. She said I would have to get it myself from Telkom and that I would have to cancel the contract which I did verbally with their cancellation supervisor. He then called the next day to inform me that I am bound to this contract because I am the one who called mweb, I have since asked him to send me a clause in their contract that stipulated that or get someone who actually knows what the contract said since he couldn't answer most of my questions relating to the contract. To date I haven't received anything from them, my guess is they would want to delay so they can claim the contract cancellation days have lapsed. I also wrote them a cancellation letter on the 30th April which they have have not acknowledged since they want to bind me by hook or *****