Poor customer service

I am having a really negative experience with MTN. I am in the process of immigrating and want to cancel the MTN contracts on my name. On Friday the 7th of July I went into the Clearwater Mall branch which instructed me to phone the 135 number to get a clear settlement amount. I phoned the number and they gave me the settlement amount which I then had to settle in the branch. I drove back to the branch to settle the amount in full. The branch then told me after settlement that they can not cancel the contract I have to phone 135 again inorder to complete this. Which I did. Friday 7th of July 2024. They told me they cannot cancel the contract as they are having problems with the system, I must phone back on Monday. Monday 8th of July I phone back. I spoke to 8 different people with multiple different excuses of why they cannot cancel to the balance that I payed on my receipt is not the balance reflected on the system. However I received an sms from MTN stating they received the payment an it was the amount on my receipt. I feel like they are very quick to take your money but don't want to serve you. They are coming up with multiple excuses not to cancel the contracts after I payed the settlement amount which means they will carry on deducting the debit order, which is *****. As I want to cancel the contract and have settled. I spoke to people one being Norma who hanged up the phone in my ear. A person called Mike Jack who said he cannot serve me now I must phone on another day. The more I emphasize that I am leaving the country and closing my bank account so need this sorted out the more they ignore me. Now when the debit order bounces then they want to blacklist you. I am angry and frustrated