Bad service and trying to ***** from me!

I am extremely unhappy and cannot seem to have closer on this matter. My cellphone contract was nearing the end in November last year, I was told to send an e-mail to cancel after I had already given the instruction verbally. After that call my last debit did not go off, and they suspended my service. To date my contract has not been cancelled and I am now in arears for payment since November? I E-mailed them in November requesting the cancellation and still this was not done. I have been calling since last year and they keep telling me to send an e-mail - the e-mail response just informs me that they can cancel as I am in arears. I am unable to speak to a manager when I call or even their complaints department - as I'm told its the same people??????