Impossible to cancel contract

I went to mtn to cancel my contract before I left South Africa in October of 2014. The branch told me to call their number. I called the number and got redirected to sen an email to retentions. I sent email to retentions with no response. I finally manged to get hold of somebody who said they would send me the details to cancel. Nobody got back to me before i flew off.<br> <br> I waited until my contract expired and then cancelled my debit order as my account has not been in use for 6 months and I have no way of contacting anybody to cancel weather this is hidden to the point where the customer just gives up or gross incompetence. <br> <br> My debit order got reinstated and keep taking money again. I have sent an email last week to cancel and have received no response.<br> <br> All I want is for my expired contract to stop *****ing my money for an unused sim.