I regret associating myself with MTN

I am highly disappointed in MTN and I have been to their offices a number of times trying to cancel a contract because I didnt receive what I was promised. A sales agent from MTN called me and offered me a phone (Huaweii Y7 2018) on contract for R250 a month, I was interested and accepted the offer, gave the sales agent my details and address for delivery, which the delivery arrived a month later, to my surprise I was sent two phones but they were ZTE A110, I immediately took them back and was told I would be contacted when the contract was canceled (August 2018), September 26 2018 a debit order of R179 goes off to MTN for phones that are no longer in my possession, I went to Capitec and reversed the debit order cause I dont own those phones and MTN has even bother to rectify the mistake, I went and asked about it at Garden Route Mall George MTN Branch and they put in a complaint to head office. I tried purchasing a new phone only to find that my contract is still valid and is unpaid, I requested it be cancelled and still havent gotten a response till today, MTN is making me seem like I dont pay my accounts and it has caused a truckload of personal loans to be declined. I dont know who to complain to anymore because Ive tried all my options. Someone please help cause Im only 22 and will need to take loans or items on credit but I wont be able to cause of MTN negligence. All I want is my contract cancelled that is it, no more nothing less. And I am not the only one, there has been alot of people I know complaining about the same thing and there are people who are given what they are promised. Thank you