Vodacoms ****py service

I’ve been with vodacom for the past 2 years and I’ve never missed a single payment in this period, however when trying to renew/upgrade my contract vodacom refuses to provide me with the deal I’m looking for as they say my portfolio is too low.

I did check on my credit report and it’s perfect no missed payments at all however they still refuse to assist, I’ve been transferred from call center agent to various different departments with no help whatsoever all they do is transfer the call.

I would like to find out what’s the real reason why I can’t upgrade before going to another service provider.