Converting Existing pre-paid Number to Contract

I have been a Vodacom customer for over 20 years. I recently attempted to change one of my numbers, a prepaid number to a contract. I ordered an iPhone 7 pre-loved online. Contract was approved and I received the new phone by courier. When I attempted to move my prepaid number to this new contract I was told it was impossible, I should have requested this during the online ordering process, this was not mentioned during the process. I had to cancel the new contract, the phone was collected and once received I could open another contract by phone and ask for the prepaid number to be used when opening the contract. I have attempted to open a new contract several times. Initially I was told I couldn't as the cancellation had not been processed. The people I speak to tell me I will be called back the following day. This does not happen. Today when I tried to call I was told my number had been blocked as I had called too many times. I would not have called so many times If my problem had been resolved. Using another number I was told my score has been reduced as I had returned a device, I do not qualify for the contract require anymore. There is no stock of the device I want, Vodacom are not expecting any more stock but I can be put on a back order list, I have reached my limit on the number of contracts I can have with Vodacom. Whichever of these stories is correct I do not know. The latest status is I should call back tomorrow to check if I qualify for "Decline Review" I previously qualified but as I returned a device through no fault of my own I don't anymore The crazy thing is should I go to another service provider I could open a contract and port my Vodacom number to the new service provider. I wish to remain a Vodacom customer but you are making it very difficult, if not impossible to do so.