MTN South Africa

I have 2 LTE contracts with MTN and the one contract has ended in October 2022 , I have recently requested to cancel this contract 3 times via telephone once went into store and have sent a email which I am awaiting a response, I am truly disappointed with the service provider and I would actually like to cancel both LTE contracts , the 2nd one ends October this year , however I would like to end both because of the horrible service I have received the last week , they still have not cancelled my contract that is due cancellation , if I phone customer care I get told they will call me back or I get cut off