MTN is so UNPROFESSIONAL

MTN is so unprofessional, I have a contract with MTN and my services were suspended as a result of outstanding balance. On the 25th of January an amount of R369 was debited on my account which was the right amount that I pay monthly. Then on the 10th and 11th of February amounts of R500 and R352 were debited on my account and I enquired what those payments related and I could not get an answer from them. I ask for a refund of one debit order and changed my mind and decided to reverse the two debit orders. I called MTN letting them know and asked them to cancel my request for refund. MTN still refunded me R500 while I reversed it. Now I am being told that I owe MTN R523, I understand the R500 and therefore I made payment yesterday however the R23 for debit order reversal is not my cost as they incorrectly debited by account. it is just *****. I ended up opting to make payments cash as I don't want any debit orders. Now my services have been disconnected, I cant use my phone. I just want to be out of this contract, I am seriously done with MTN this time.