Account cancelled but billed a month later

I visited the Telkom store on 02 December to fully pay up and cancel my account. I was told this can only be done over the phone and was subsequently asked to cancel my account online, which I did.<br> <br> I received an sms on 03 January which confirmed the cancellation of my account (ref no:***). I have this sms as proof of cancellation. On 17 Jan I received a bill for the period of 15 Jan 15 - 14 Feb 15 despite the cancellation. Upon calling the call centre, I was told my line is still open and has not been cancelled, with no attempt to look further into the issue or escalate to a supervisor. <br> <br> This incident needs urgent attention as it is a gross administration mistake.