Mtn poor service - dissatisfied client

The service is the worst, they list me for R136,00 what was I paying for when i asked the serviced to be canceled years ago but today I hear it has been changed to cash payments, I have had an MTN account for more than 20years and have never ever made cash payments *** please I need an urgent explain and letter of apologies and i want to know who and why my account was changed. I also need to be cleared from the bureau and a paid up letter. Contact me on my email that you should have on your records.