Disillusioned by Vodacom's Refusal to Refund Contract Claim

I discovered as I was nearing the end of my data contract with Vodacom that somehow I had lost track of the fact that my contract ended almost a year before. When I came to this realization I asked a Vodacom shop (Menlyn) employee that was assisting me where I could claim the extra money I had been paying and he gave me " ********** " to call. Upon calling the number, I was then referred to another number " ********** " to cancel the contract because I was no longer interested in the contract firstly due to finding out that Vodacom does not let data contract customers know that their contracts are finished and secondly because I got a better and cheaper deal at Cell-C. After calling the contract cancellation number I was told to call " ********** " because every Vodacom consultant I spoke to from the shop in Menlyn to the call centers, they all agreed I was owed an amount of around R1500 (although my calculations showed more than that. After calling around 8 people (two individuals whose names I cannot remember, Anisha, Palesa, Sipho, another person whose name I cannot remember, Bongi and then Selinah/Masabata Lepota), I have brought my complaint this far. From the time I called the last Vodacom number since December, I have been asked to supply Proofs of Payments which I have, but I keep being given the go-around and cannot do this anymore. I don't know what other paperwork it is that I need to submit. Please assist. My account number is I ********** -3 and Reference#: ********** ********** 9.