********** updgrade and cancellation request not actioned, credit listed and Collection agent calling me frequently

My experience with Voda account has not been good at all. There was a confirmed ********** updgrade on my 5 gig account which expired some time last year May/June 2016. To my surprise after expiry of this 24 month contract (5 G worth R249), some ********* **********ly upgraded my account without my approval and a surprise debit order of R679 went through my account which I reversed. I raised this matter in writing in August 2016 and in November 2016, ***** was indeed confirmed. And I requested that this account be cancelled all together. Spoke to different *********** staff regarding cancellation request and no one ever cancelled this facility and now i am being held responsible for their incompetence. I continue to receive calls for supposedly outstanding amount that I owe and have been threatened with credit listing and have even gone to an extent of being referred to collection agencies. I don't take this kindly and are currently exploring other avenues including invoking National Credit Act (NCA) and Protection of Personal Information Act (POPI). NCA is related to the contract renewal after expiry of the initial 24-month contract which requires that written notification be sent to me and I must agree to this continuation of a contract on a month to month basis while POPI is relating to usage of my personal information to perpetrate ********** upgrade. Otherwise how else did the ********* manage to get my personal information if it was not compromised by Vodacom? Someone must be held accountable and so far I have never received feedback on what really transpired (i.e. who perpetrated *****, how was it perpetrated to ensure mitigating controls are put in place going forward, what action was taken with the perpetrator, etc. I won't be bul**** to pay something that I don't owe. I am currently a prepaid vodacom customer and I am really reviewing this marriage as I continue to hounded by vultures. I won't have a problem severing all ties with vodacom and start with another service provider. Unless someone comes to me and explain why they allowed a situation to go this far and resolve amicably, Vodacom is on the brink of loosing one of its loyal customers.