***** query of a none client with Cell C

On the 1st of February Cell C decided to debit R70 out of my account, when I found this out I queried this with my bank which is Capitec, they then told me I should phone Cell C to query this so I did. I was on the phone for 3 hours being transferred to different people that work at Cell C which my details were not in there system. They said it would be sorted and that I won't have money going off as I am not a client with Cell C. So again on the 1st of March Cell C decided to take off R939 out of my Capitec account again so I went to my bank and told them what has happened the saw that I did not agree to any debit orders with Cell C, the lady that helped me at Capitec tried to get ahold of Cell C for 2 hours which at the end they said they could not help as they don't have my details on the system. So finally the lady got ahold of them and and emails to the ***** @Cell C email and sent all the information. Today 17th of March I got a phone call from the forensics @Cell C where I was told that my mother has given them my banking details so they could take money off my account. I told them that it is ******* for someone to give details out that is not the person's she said well that's how we got it. I phoned my mother and she did tell me she didn't give my banking details out. Which explains why they can't find me on their system. I phoned the forensics back and told them I want prove that there is a signed contract stating they can debit off my account and I also said that my mother has been paying them every month for the past 3 years and have sent references, bank statements of the payments with the banking details.