*****ulent roaming charges on my contract

*****ulent roaming charges on my account : 071........ Good day, I am on MTN contract R495. I recieve data and minutes and after the data and minutes are finished i am on pre'paid.I was surprised to see a debit order deduction of around R2900 from MTN for the end of JAN . I reversed this debit order as I thought it was an error . I checked my bill and I saw a roaming charge on the number ***. First and foremost, I do not use this number at all. My wife uses the main account number 071....

and I use ***. We have not left the country and have not been on roaming. I called mtn and was told the system is down and they can not help me. May you please track who is using this number and have them pay this charge as I am not responsible for this. Secondly my contract does only gives me data and local call minutes. How is it then this roaming charge was allowed on my contract. If I am out of data or local call minutes I have to top up. I called the *** number and some stranger answered it. May you kindly get to the bottom of this and fix my account. Looking forward to hearing from you soon. Kind Regards Hilary