MTN takes money from non-clients bank accounts

A debit order of R13,401.94 was taken from my account on 31 August. I contacted the Customer Care department which informed me that I have 2 active numbers under my name. I responded that have never been a customer of MTN. Since then, I haven't heard anything back to resolve the issue. On 30 September another amount of R64,756.78 was taken from my account. There is no other way to make contact with them except through e-mails which they don't respond to.