MTN ******ion

I have had a contract with MTN and ported to prepaid and opened a me contract but I been billed for to contracts ,but I only have one active. My contract came to an end in may 2018 but cannot cancel it or port it to prepaid because it at legal. I went to the main store in pavilion explained to sales person who clear did not know her duty instead she shout at me to listen that the account with legal , I told her I needed to see her manager and both were in back and teamed up against me while I'm being held hostage to a contract that expired and I don't want and I still got to deal with *********** staff. It really pathetic the service ,I want this resolved and no one can help so I can get out of this contract with this company ,I advise others from experience don't go this root you regret it they quick to sign up and hold you hostage once they have your businesses then you be taken to cleaners