MTN Cancellation Nightmare

I have two cellphone contract that I would like to cancel. I have been to a MTN shop but was told that I must phone 135. If I phone the number I am put through to cancellations and that is then end of the story. Yesterday I held for 45 minutes when I got through I was informed that the system is down and I have to phone again tomorrow. This morning the same story. I was put through and held for 20 minutes. I decided to phone again and ask is there is no other way - once again the person told me that I will be put through I am now again holding for 35 minutes. This is really unacceptable!!!! I need to cancel two contracts and it has taken more than two hours from me and have still not managed to get it done!!