Can't get cellphone contract elsewhere

On 2014/03/03 I cancelled my cellphone contract with Vodacom due to poor service. I paid the premature cancellation fee in full and it was said to me by Rochell Carolus that my account is zero and I owe Vodacom nothing. Now every time I try to get a cell phone contract on my name they decline cause apparently I still owe Vodacom 400 odd rand. This is ********! How do I still owe Vodacom money after its been said to me nothing is due to Vodacom by me?! This is why I left Vodacome cause they drag money out of you!! I want someone to phone me so we can sort this matter out and to clear my name ASAP! Otherwise I will be taking this matter further!