MTN cancel this contract immediately!

I am so dissatisfied and disappointed in MTN. I would like to request an immediate cancellation of my contract. You hounded me for months to upgrade my phone. I finally upgraded to an iPhone 13pro 256gb in graphite black, but when the phone got delivered it was gold. The call centre advised me to take it to my nearest MTN store and get the IRMS number. When I phoned back with the IRMS number I was literally sent from pilar to post, given several numbers for cell network, non of which worked. Eventually I resorted to Facebook Messenger. Still, more than a month later, I still don’t have any feedback. No-one can tell me what’s going on or when the upgrade will be reversed. I am paying for something I don’t even have, so please CANCEL THIS CONTRACT IMMEDIATELY. I cannot keep trying to get feedback from you!