What upgrade????

I was contacted by Summer mobile on behalf of MTN sometime in March when I was due for a contract. On the call I specifically asked if whatever changes they were making on my data plan, would I still be able to upgrade my handset and was told yes I could. Lo and behold I go into an MTN shop, ready for a handset upgrade and I'm told I'm only due for an upgrade in 2021.Now the consultant at the shop also advised that he has come across a lot of customers like myself, so what baffles me is why can't MTN take back their database and call all of us who were "upgraded" by this Summer mobile and verify if we are aware of the situation, unless of course if they're cashing in on it. I then called the call centre and spoke to a Manager who escalated my query on reference *** and advised that it would take 3 working days to get feedback. I called AGAIN today, a week later and I'm told the person who escalated my query is not in today and told Sbahle she has till 12:00 to resolve my query, it is 13:04 and no one has contacted me....WOW!!!!I've been an MTN customer since 2005, but I think it's time I ported my number to other networks.