Mtn mondo contracts

Last year in October I was going through my credit report then saw that there was a contract opened at MTN Mondo with my name.I called them to query it and informed them that I don’t know anything about it.Request was made from me for n Affidavit and copy of my ID to conduct an investigation .As part of the investigation Mondo came back to say that I am liable for it according to their records I accepted that contract after the agent that I spoke to assured me that he can hear that my voice is totally different from the one that accepted that contact . I then asked their process of opening contracts for ppl n requested a documents that person used to be approved for that cellphone contract . On top of that I have to call them for follow up on my case no update or anything from them and I just wonder how many vulnerable customers are they de*****ing without doing a thorough investigation..they say I opened a contract but could not even provide me with a copy of documents used for that cellphone contract ….Today after receiving a call from the debt collector saying my account has been handed over with an amount of 36000 I decided to call mondo to find out about my case ..call was hang up n no call back was made reference number for that query is RCO446277 I wanna know how do they approve contract without proper conduct of verification being done ..Question that I asked was is it making sense for me open two contracts and that phone was delivered in Pretoria which is not even my address to begin with