Upgrade nightmare!!! PATHETIC SERVICE HORRIBLE!!!

I received a phone call from a call centre agent advising me I'm due for an upgrade , this is 3 weeks ago. I was interested in an iPhone I told her to load the latest iPhone she assured me all is in order she will do it .I should expect delivery after 3 days. After 4 days I called the call centre to check on my order. The order was not done... oohh ok. Thandeka Mdlovu does the order based on what was on the system. When she recaps the call she tell me its an iPhone 10 Blue in colour after I was advertised the latest iPhone black in colour. I asked her not to deliver the device as its not what I'm looking for. the call gets cut I never hear from mtn. Day in day out I call them to follow up they send me from pillar to post till today I still have not heard anything from mtn. Last week I finally get hold of Thandeka Mdlovu absolutely rude , I asked to speak to her manager she asked me can she speak to my manager.... I actually thought someone was pranking me I dropped the phone and continued with other things. I called today I was told Thandeka's manager Shareeka ****inson will contact me... I'm yet to see what will happen. To make matters worse I was debited 3 days ago for a phone plus service that I have not received... It must be very nice MTN. The only thing I want now is to cancel the upgrade I will get service somewhere else, even that is a problem they can't cancel the order before they get the device that did not even reach me. So frustrated ... I need my money and cancel this upgrade I WANT NOTHING DO TO WITH YOU MTN- Huge inconvenience .