My Name On Credit Bureau for Wrong Reasons

Dear Hello Peter<br> <br> This network has put my name on Credit Bureau because they saying I owe them money which I completely fail to understand, my account A*** is a contract phone which they were debiting monthly, contract expired in June 2014 however I only cancelled it on June 2015, now they telling me that they didn't debit money in January 2015(reason being I don't know), I made a cancellation in June which was accepted(How do they accept cancellation when I still owe them?), Since cancellation they never did any debits which to me confirms that cancellation was successful, but not even a consultant called me & told me that they couldn't cancel because I owe them, they kept quite until my account was handed over to legal team in October 2015, they saying I owe them around R400 or more so I have to pay thm to clear my name from Telecommunications industry<br> <br> Person handling my case is (Sibusiso Nkgothwe) his address is [Email Removed] voiceline ***)<br> <br> Note that the phone on same contract was for my grandma & it was ******(Sim Swap was not done), so I haven't been using that number at all, my contact is ***, all I want is for MTN to clear off my name