Upgrade struggles

Vodacom has always been good to me and for this reason I have more than 2 contracts with them. But this is now the second time I try to do an upgrade on my exsisting contract and it wont allow me to take the deal. Only on a new contract. The excuses range from its a downgrade. I maybe behind on my payments,etc. New contract I qaulify so its not the problem and I have been batteling for almost 2 weeks now. The deals they offer me on upgrade is not what I want. Please Vodacom can you sort this problem once and for all and not tell me 48hrs just to tell me today another 4 bussiness days. Its so simple I qaulify for upgrade. I have money in the bank. I have never missed a vodacom payment in 20 years and you can see all on your system. What happend to your service delivery and keeping your loyal customers happy and retaining them?