Telkom Billing

I have a contract with Telkom. i made an upgrade last year September, from their first debit order which was in September iv had issues of not being debited and being charged the penalty for their mistake. I have made thousand calls, i have emails from their *********** staff advising me different things as to why i was not debited, i have all the proof from their staff members who i spoke to and asked them to request their managers to contact me and no manager has ever contacted me, instead they send me a text after days saying my case has been resolved. I took my phone at Umhlanga Gateway initially, and did an upgrade in Durban central branch. At gateway they know me, i do not have to tell them my query because im there every month and they know me. I have never gotten any assistance from the store, they just request a call back and let me sing my song every month. I have been paying the penalties ever since, opening cases i never won. Telkom owes me so much i have even suggested that they take their device , and keep all the money that i paid so i can have peace in my life with no debts, they refused to take the phone they said i must pay the outstanding balance if i want to cancel the contract. There is nothing that says i have to go stand in long ques on my contract with them so i can do manual payments, but that is what i have been doing every time they forget to debit me. The famous line from their staff is 'i can not see why you were not debited' , they never have answers for anything, and they are not scared to say I DO NOT KNOW. If someone can see this and advise what to do, i do not want to have partnership with Telkom, they have taken so much of my money. June and July i made a manual payment since n seen them proof of payment and they confirmed the payment was received but this morning i received an invoice saying that by 31 August they need R797 yet my monthly installment is R399. Regards, Nokuzola Hlengwa 074......2288