Telkom is bulling my bank account and i am tired

I have an agreement with Telkom mobile to debit my account for my instalment for services on the 25th of every month as i get paid on the day.On the 24.11.2017 Telkom decided to debit my bank account without prior arrangement and it came back unpaid due to insufficient funds. My bank charged me R100.00 for debit order not provided for .And Telkom billed me an amount R200.94 for and unpaid also. Later Telkom re-debited an amount of R159.00 on the 30.11.2017 which was successful ( Now that my salary was in on the 25th Saturday) . I called the call centre and spoke to a call centre agent by the name of Sihle Ngwenya who was at first arrogant and certain that I owed Telkom and it was their policy to debit before the agreed date should the day fall on a weekend or holiday. I told him that's not the law as per CPA . He then after a long argument logged a case ********** 8. I called before they debited to follow up on the progress on my query. I was told the case was still pending and allocated to someone who will call me later before end of business on the 22.12.2017 . Which I didn't receive any call to my surprise my account was debited for the subscription amount and the penalty . Guess when two days after the agreed date due to the fact that it fell on a holiday . So I called them to enquire the matter i was told a supervisor will give me a call . I am still waiting. With the record of ratings listed i doubt if i am gonna get a call from this corporate bully of a company . But neither way should they not respond i will hit them where it hurt most buy returning their debit order till we meet in court.