Says 199 but paid over that for 2 months in a row

I got a portable WiFi from a call center agent who told me it will never cost more than R199. Name simon ref for call:***. On the 27 of October (my birthday) I get a deduction of R270 odd from my account. I called to complain the guy tells me I can't only pay R199 that there is no way to limit the device to use no extra data. That the minimum is R50 extra which I have no choice but to pay. I laid a quiery ref: SS-7NTB-O1. No one ever got back to me. This month my account is deducted with over R300. Not only did no one bother to attend to my problem. They did not even bother to limit my acc to the minimum value. I am now stuck with paying for goods I cannot return. I no longer want this product. I don't want it if I cannot pay only the agreed upon price. You should have this on record if your calls are indeed recorded. I did not sign a contract. I made a verbal agreement with someone over the phone and you have not honoured this agreement and are debiting my account with money I cannot afford to be debited. I am disgusted in cell c, your service and the fact that I cannot return this product. I don't want it anymore. I want to give it back. Ur sales people r defective.