Daylight robed by cell c

I've got contract with cell c,for the past 2yrs I was paying 223r but all of a sudden on the 6th of January, they deducted 397r on my account,when I ask cell c why,the said I've join company called Getmore which I don't even know what is that company stand for and I don't even know why Cell c add them on my account without even informed me,so,they gave the number for that company, I called the company and they said I'm not on their system they didn't deduct any money from my contract,so,they can't able to cancel something which is not exist,I called cell c again and they said they've got nothing to do with that I have to pay them even though I don't know them and they also don't know me as well, I thought my contract it's between me and them but now they include third-party person without my knowledge,now I'm scared cause it's clear that my bank account it's not safe with cell c,I gave them my bank details and they gave it to their friend for no reason, please somebody help me, those people who work at their call center they are so rude and I think cell c need to train them they are not professional