Extremely Bad Service and incompetence!!!!

I had an account with Vodacom which ran it's 24 month due course. After the 24 months I started receiving sms's that my account was owing, when I called they told me the account was now running on a month to month basis and for me to actually cancel the contract I would need to pay the R800 amount in arrears which I had been getting billed for post the 24 months of the contract, which I agreed to pay and paid. Post that there was no correspondence about any amounts owing which made sense because I had paid off everything in August last year. Last week, when I am trying to buy a house, I get declined because Vodacom has placed me on ITC as owing R251!! This is without any correspondence with me AT ALL. When I called the legal department today I get told that when I was given the settlement amount of R800, in the background I was already being billed for another month, which they failed to notify me of, furthermore they go and blacklist me on ITC without any communication with me of any further amounts owing!!! I get blacklisted for a mere R250, which I was never owing in the 1st place, for a contract that had ran its due in any case, COMPLETELY DISAPPOINTED BY VODACOM AND WOULD NOT RECOMMEND ANYONE TO GO ON CONTRACT WITH THEM!!!!