Upgrade decline

After being a client of MTN for almost 2 decades, upgrading every 2-3 years and even taking an additional contract last year. Not skipping any payments or late payments...i have been declined for my upgrade due, because of not passing the credit vetting, which has never happened before and in October i was told by the sales agent that i will be able to upgrade because my credit is in good standing just to be declined in-store yesterday and online this morning. I think its time move networks.