POOR SERVICE AND NEGLIGENCE

I took out a data Sim with mtn. All was well until one month they were unable to debit my account. I then tried numerous times to call and arrange for payment, without success. At the end of that month, I found that my contract had been altered completely - it was now a data and airtime aim with a different premium. Once again tried contacting them, was sent from pillar to post, no luck. Now, they supposedly received a new order from me, different package AGAIN. Nobody is communicating with me regarding all these changes. I tried calling and emailing countless times with no luck. I'm dissatisfied with the service I'm encountering with mtn and frankly, tired. Poorest service yet!!!