Perturbed customer

Good day I am a Telkom customer and at the moment I am extremely disappointed in the type of service I have been receiving for the past few months. My account is being debited double triple my installments I have been at the Telkom branch Tokai where the consultant advised me to put a usage limit of 1.00 in my wifi router Sim which I did to add he was very ****y and arrogant besides that yet my account is still being billed double triple I then called in and the lady who helped me on the phone assured me that the month of October my account will be sorted because the usage limit only starts this month and yet I was billed double again. I am very upset and I feel I just want to cancel the entire contract. I can't afford to be loosing all that money every month and I hardly use the router. Please assist