Pathetic Customer Service & ********* Billing

I received my statement and called the customer care and spoke to Sello. Few issues and concerns which I would like to escalate: Sello could hardly speak properly; I kept telling him that I could not hear him as it sounds like he is speaking right into the MIC, I advised him to maybe move his MIC away a little from his mouth, as that could help me hear him better. I called to enquire why my bill is double the amount of what I usually pay, his response was that Cell C removed the discount from my contract cos I cancelled the contract, however I was not informed of this when I placed the notice on the 10th October. My contract is currently still valid until the 8th, as I was told, so why has Cell C charged me double when I actually gave 30 days notice as required?? Sello refused to allow me to speak or explain or even ask further questions. When asked for Sello's full name so that I can escalate this, he refused to provide his surname and said that he cannot provide this to me, thereafter he put me on hold and I'm not sure why until I hung up. The service from Cell C is rather shocking and pathetic, I would like to escalate this billing issue as I was not informed of the discount been removed, in fact on the 10th, I spoke with Bulelwa and she even confirmed the amount of R98,10 +15% VAT, however my bill is over R200 this month. WHY? Notice was given and I do not wish to upgrade my contract hence why I cancelled after giving 30 days notice. I would like for this to be dealt with ASAP as I will contact my bank and stop the debit order as I did not sign up to be charged double the amount. In fact it's day light *******, as my contract ends 8th of the month but I'm still been charged the full month's fee PLUS the discount was reversed, instead of it been pro-rated till the 8th....