billing for no device in possetion

One again I was billed for a device I don't have and it was given over to telkom in Canal Walk Cape Town. I was put on hold and this whole process was dragged out ,Neo (cancellation consultant)keep telling me she will get back to me and never do,then Eric (finance manager)keep asking for the sim card number I don't have ,I have told him several times I don't have the device what r Telkom's staff trying now I was billed this month and where as I asked Eric and Neo if this would happen both of them have promised me this matter will be sorted . I'm so angry that this matter can't b resolved and they taking my money *****ing my money for a device I don't have