Too much debit

Good day,<br> <br> I have a big problem now with Cell C, I think whenever they feel like debiting any amount at the end of the month on my account they just do so, this month an amount of R486.99 was debited and I only know that my debit order is for R299.00 imagine if I only left R300.00 for my debit order to be taken, it means it would have bounced and yet Cell C would bill me or even block my phoned as they did last time. I called right after they deducted this big amount on my account but to my surprise the lady I spoke to told me it was something called Get More Real Deal that debited my money, and you know I cancelled that service long ago I think in Feb this year, so I want to know who authorized them exactly to deduct on my account, I want my money back please I do not want to be told that it would be deducted from the next debit order or anything else, I do not owe anything to this Get more thing, and Cell C, without this Get more they also debit R369.00 every single month and when I call they say because my account was once in arrears so they are behind with their billing, so for this month I was billed R69.00 for April's debit order and so forth, please assist.