I HAVE CANCELLED MY CONTRACT BUT MTN STILL BILL ME

I have a contract with MTN which expired in April 2015, on the 20 April I sent an email to customer care to notify them of my intention to cancel the contract . <br> <br> On the 15 May 2015 MTN deducted my monthly subscription fee. I have tried to make contact via their contact centre but I was kept on the holding line for too long, then I decided to forward my original email to them on 18 May 2015. <br> <br> Today 28 May 2015 I phoned call centre 808, only to be told that my contract is not cancelled, and they can't find the email I have sent, so they are going to deduct the subscription fee again in June, so my contract will only be cancelled in July.<br>