Unhappy Vodacom Customer

I was Due for Cellphone upgrade on the 13 June 2018. I had vodacom match a deal with Cell C for my upgrade and it was approved. I went into the store to finalise deal and they refuse to give me the contract saying that there were other problem. I have been on this Red contract for 4 years and now they say I don’t qualify after they sent me my upgrade date and also matched a new deal with Cell C and even sent the confirmation. I am totally disappointed with the service I am receiving from Vodacom and the way I am being treated as a customer especially someone with a higher contract.