Worst Service Ever from Vodacom and their Consultants

I am currently due for an upgrade on Vodacom. So I apply for the upgrade online and it states that due to my credit profile there is only certain contracts that I can upgrade to which some of it actually is more expensive than the current contract. I had this account with Vodacom for 20years now. Also I have now been trying to contact them on a daily basis and then end up or on the chat line or where they are calling me without a reasonable answer of why the system is not allowing the contract but that the systems allows for a more expensive contract. Today's feedback from the consultant was that I should go to the Vodacom Store and then they would contact them and might then be able to assist. How ridiculous is that??? I somehow want a valid reason for this situation. Also I then requested that they then close the contract which they are also not willing to assist with.