Another unauthorised charge

Yet again Telkom added an unauthorised charge to my invoice for a 3rd consecutive month. This applies to the mobile number ***. As in the past 2 months Telkom has added an amount of R349 to my invoice which i did not request for or authorised. I contacted Telkom on 4 December 2015 to compain about the additional charge. I was told that it will be reversed so that payment will exclude the unauthorised charge. I was also told that I will be contacted by the relevant department. The Telkom reference number given is ***3. I am yet to receive a call from Telkom. I do not want the situation to reach the stage where I must pay the extra amount and have the charges reversed in the following month.