Unhappy costumer

I am very unhappy with Cell C at the moment I had made a payment into Cell C account that was June until today they cannot find the payment after sending proof to different email calling them the simcards are blocked for 3 months instead of finding the payment and correct my account they cancelled the contract without communication to me now I am owing Cell C a lot of money that I do not have I will never again took out a contract with them I am really dissipointed in Cell C though they are better than others networks what are they doing to find my payment and now I have to pay double