MTN poor service

I requested the cancellation of my MTN contract. I have given notice on the 16th of October again after the first attempt a month earlier. I phoned 135 on the 18th November to check if the cancellation was completed and to be on prepaid with the same number. (Luyolo) assured me at 09:15 that this will be effective the same day. I checked again today the 19th of November with (Buhle) and were told the contract will only be changed on the 16th of December. Thus, *****ing another month's subscription as my contract ended on the 16th of November. The service agent even asked questions of a personal nature why I want to cancel the contract. This is totally unacceptable, and I want MTN to take immediate action and also give proper feedback.