Worst customer experience with MTN contract cancellation

I have been battling to cancel my contract since the beginning of November 2025. It is very difficult to access the retentions department. There is no option for contract cancellation on 135 customer care number as this number is listed as the number to cancel your contract, also there is no option to speak to a consultant; I eventually went to the MTN shop where they gave me a *** number which was answered after being on hold for almost an hour. The MTN consultant says is 30 days notice and another says is 20 days notice to cancel contract. I eventually submitted my cancellation on the last 20 days, where the new consultant told me that I was supposed to submit the cancellation 30 days before. I eventually submitted my cancellation with ref ***, it was supposed to end on the 12/12/2025. On 13/12/2025 I receive an email saying that my contract ended and it has been converted to a month to month with a higher amount than what I was paying, something which I did not request, I requested a full cancellation of the contract and the number as I no longer use the number. The number concerned is ***. I regret doing business with MTN, they have the best product but the have worst customer experience and I think they are doing this on purpose. They do not want you to cancel even though the contract term has ended.