failure to cancel account

I closed my Telkom account on 14 April 2015 and payed my bill in full. I received another bill and when i inquired , the account was still active. I, yet again, asked for the account to be closed. This was suppose to be the final account. On 17 June 2015, i went back to Telkom to make sure that the account was closed and to ad too my frustration, it was still active. The employee opened a dispute and told me it can take up to 4 weeks before the dispute will be finalised. On 8 July 2015 I inqui r ed again, finally, the account is closed, but I still received a bill for R847.92. Really ? I had no Telkom service since 14 April 2015,