BAD SERVICE

According to ITC and Experian, I owe money to Mutlichoice. But, when I phone Multichoice, I am told my account is in credit. I asked Multichoice to update it with ITC and Experian, but they cannot put me through to the Finance depart. They can only E-mail them. I CAN ALSO E-MAIL AND HAVE DONE THAT, BUT THEY DO NOT RSESPOND TO MY E-MAIL. I want to buy a car, and the bank tells me that I will not be able to get finance unless Multichoice updates ITC and Experian. Multichoice now tell me I have to wait 30 days!! So, now I cannot work, because I don't have a car. And I will probably phone after a month to hear that they have not done ANYTHING. I don't know what to do now.