MTN SA IS A ****MMMMM!!!!

MTN is a ****. I've never had any contract with MTN and never used MTN for the past 10 years and to my surprise I have an outstanding amount of R12 000. How so?? When I enquire no one is able to assist me and that reflects bad on my credit score!!!!!!!!! YA'LL ARE FLIPPIN' ****MMMSSSS!!!!