Shocking sevice after being loyal for over almost 30 years years

I have been with MTN since inception of the telecoms industry 1992. I have been trying to upgrade my contract from November last. There was initially a stock issue, after numerous calls to the store because they never call you as promised, NO ONE get back to you. Absolutely shocking sevice. Eventually after back and forth between Pavilion Bluff and Gateway. I have settled on a deal , to be told I don't qualify for it. I have never defaulted on paymen ever. Does MTN.need business or are they happy to lose a good paying and loyal customer. I will port my number to a provider as I am out of contract