Cancelled but they still attempt to bill me

I cancelled my Johannesburg Telkom line on 7 April 2015 at the Sea Point Telkom store. I received the cancellation reference number of ***A. Telkom billed me for my final month, as agreed, and everything seemed fine. <br> <br> Then they sent me *another* invoice for the following month. I tried to go confirm the cancellation at the Sea Point store twice in two days, but both times their systems were offline. <br> <br> I put a stop-order on this debit via my banker at FNB, as I suspected they will attempt to debit me invalidly for the R488 I used to pay them. <br> <br> Today I received *another* bill, apparently they want to bill me for July 2015 for an amount of R747.25.<br> <br> This is for account number ***, phone number ***. <br> <br> I wish they would just get their act together, their incompetence is not my problem!