MTN - ********** service

I have been a customer of MTN for 25 years. I upgraded my package end of last year and there was an error as they issued me with another contract, instead of upgrading. They listened back on the recordings and admitted to the error being on their side. I was then told the only thing they can do is for me to cancel the new contract and return the Iphone as they don't have stock to upgrade my existing account. I then said well I cannot be without a phone so I told them just to leave the 2 contracts going. There was an error and my bank returned the debit and MTN the suspended my account. They double debited my account the following month and received the money on the 1st February 2022, but my account is still suspended. I have called in numerous times and spoken to a few people have said they cannot assist and directed me to the 135 number, which is useless!!! I then got through to the cancellations department and asked for the manager to please call me, in order for them to hopefully be able to steer me in the right direction other than the 135 number, This was 6 days ago with still no response. I logged a complaint via email to the customer care department requesting someone, a human being to please call me to discuss, this was 3 days ago and still no response. I am a single woman/parent and need my phone for emergencies, but beside that I have paid for a contract/service that I am not able to make use of!!!! Shocking service!!!