MTN *****ing money and wrongly accusing me of owing them money

MTN, *****ing your money and unwilling to assist in solving a problem THEY created. Im so tired of being harassed by a law firm about my outstanding MTN amount that I do not owe!!! I was incorrectly billed for about 6 or 7 months leading up to me closing the account. Every time the problem was rectified and I had to carry the costs of reversing the deduction from my bank, not to mention the endless calls to MTN about the amounts taken. They took nearly a R1000 more than my closed contract R99! Now, almost a year after closing the account (in the Baywest store), they say I never closed it. I threw the documentation away a couple of months after closing it. So I dont have the proof they want anymore. Baywest has been pathetic in helping me find the documentation and assisting properly to solve this matter. So once again, they say I owe them just over a R1000. Im having a rough enough pregnancy without dealing with these people! Not even to speak of the law firm that wont hear any reason and speaks to me as if Im a ********. Im at the point where I just want to try and pay this so I can move forward! Nothing makes my blood boil faster than hearing the name MTN. Tell me MTN, when you were at fault so many months during my contract, what makes you think you are not at fault now?! Clearly there is a massive flaw in your **** system. I would be embarrassed if I were you. I have never experienced anything like this. There is nothing protecting me as the consumer from your greedy company. I tried and I am so tired if the extra, unnecessary stress it causes me. All I can say is... if you are thinking of MTN as a choice for you... RUN! FAST and far away, because at some point, they will also try taking your hard earned money that you do not owe them.