No action on request

I have a contract that was ending in April already this is even before the strike started , I was advised to call in in April so I could cancel it and have the numbers converted to prepaid, I did exactly that and I was informed initially that my request will be processed and I will get a call from the respective department in that regard however that never happened, I called MTN again for the second time in April still and I was told a call was logged and I should wait for someone to call me but nothing of that sort has happened instead I got billed for a service that I requested be cancelled . I called in to query it and I was told it shows on their records that I did indeed call and it will be escalated to date the contracts have not been cancelled and I am still waiting for MTN to call me all the while I am still being billed . The ref number I was provided with is 129304,