No assistance for nearly a year!!!

I've been battling with the same billing query for the past 11 months with absolutely no resolution coming from MTN customer service as well as the legal team. I have stated my case on more than one occasion, provided bank statements at least 6 times as proof that i have been paying my contract, every time the query is passed onto someone different and i have to resent my documents, i have requested a supervisor or manager on more than one occasion, ive been to the MTN store and still have not received any assistance. The debt collecting company is still calling me asking for payment and i am past the stage of being calm now, this is by far the worst service i have ever received from a service provider, i would never consider MTN as a network carrier again. Pathetic service. I am utterly disgusted.