Overcharged on my account for 9 months with no resolution from Telkom

We had an exisiting contract with Telkom and then called to upgrade our contract to a special Telkom was running. I was informed by the sales person this is possible and was sent a router and my new service was activated. However at the end of the month instead of being billed the 799.00 I was billed 2649.00. I contacted Telkom to query this and they confirmed I been billed for 2 contracts which was incorrect. So they collected the new router and we resorted back to our old contract. Again however I was billed for 2 contracts. I queried this again by going into the telkom office in seapoint who bounced the issue back to Raymond Sabelo. This was in April 2017. I continue be billed for 2 contracts despite numerous calls and emails to telkom. I was even called by telkom to say your contract is due for an upgrade and we will refund you for the overbilling. When I called for the upgrade on the number in the sms it was unbelievable I was shoved from pillar to post. I continue to email Raymond Sabelo daily for a response on my account and never ever receive a reply. I have gone to social media, I have tried to escalate this issue and to no avail. It has been a truly horrific customer experience, I am exacerbated and completely helpless as to how to resolve this issue and am literally desperate to terminate my contract with Telkom and to not ever have to do any kind of business with them again. How do they do this to a consumer, indiscriminately debit your account month on month for 2649 without any regards for the customers needs or requirements. Raymond Sabelo needs to be questioned on his service delivery. This is now my last resort to post on Hello Peter in the hope I will get some kind of assistance in this matter.