Pathetic service from Vodacom

I paid Vodacom the outstanding amount they told me I was owing the 1st time and after that I still received calls that I was owing them, how I still don't know even today. Then I made another payment and still they told me I still owe then a few months later. I made another payment but still today when I called them 2 years later they told me I have an outstanding amount and I've been handed over to collections. I need Vodacom to fix this issue and cancel all the Nonsense they did. I need my name cleared. I can't stand this stupidity from Vodacom.