Contract expired "Discount fee doesnt apply anymore" but still beeing charged for headset

<p>Took out two contracts January 2015. Both same phone same package. Both gets billed differently, One has a straight charge for contract and service fees, Second used to get a discount on service fees although both ended up the same total, Since end of January the contract that used to get the discounts on service fees doesn't get the service fees discounts anymore but i am still being charged for the headset. So now my bill has gone up by R100 WITHOUT ever letting me know, I also got a call from a company calling on behalf of MTN and i told then that i would like to cancel my contract, I was told that i need to email. Ever since then they have stopped calling me and are calling my wife every week saying that she can renew the contract on my behalf which she refuses. I did email MTN to cancel my contract on the 5th of January but never got a response just a reference number ( ********** 1). I have tried to call twice and once was on the phone for over a hour and then the call got answered and got cut. Second time i ended call after waiting 30 min. Can you please call me to resolve this</p>