MTN refusing to reflect my payment

After struggking since June to get someone at MTN to fix my account, I managed to get a hold of a person that agreed to help me. My scenario in short - I have the official proof of payment from June 2015 stating that I paid, like every month. MTN has received my proof of payment and still refuse to allocate it to my account, and this morning smsed me that my line will be suspended in 2 days if I dont pay. Not only is it dusrespectful to a customer after 6 years to be threatened, but it is pathetic in the way that I SENT my PROOF OF PAYMENT yet YOU, MTN, choose to ignore it and threaten to cut my line. How can you treat your customers like this? I think its time to go to the media, and I warn yiu, if my line is suspended in 2 days, I will make sure the damages you cause me will be returned! Someone BETTER call me or there is going to be hell for every person that has refused to help me, I kept all the employees names and I am now DONE with your pathetic service, this is ******* and I will drag you to the ombud if I have to, YOU OWE ME MONEY, its not the other way around.