account cancelled and still receiving a bill

I sent through an email cancelling my telkom services for dsl and line on the 21st of Jan 2016 with all the correct documentation and received the following response from Telkom<br> <br> \Dear Customer<br> <br> We hereby acknowledge receipt of your fixed line Consumer Contract and Services Cancellation/Retention Request. A service consultant will contact you within 48 to 72 business hours to verify the information provided and/or confirm cancellation/retention options available...\" <br> <br> I paid my last installment of R260. which is what was owed to Telkom. <br> <br> I have now received another invoice for R354 I will not be paying this as my line should have been cancelled by now and I have not used this service at all. <br> <br> Please rectify this. "