iPhone Benefit is an upfront cash payment

I bought a new iPhone using Discovery's iPhone benefit. I have purchased 2 apple watches over the past 3 years and have used my credit card budget option for one or two big purchases in the past. I, therefore, had no reason to expect that the iPhone "benefit" would be any different. After taking possession of my shiny new iPhone it appeared as a budget item on my banking app, showing the monthly interest, the amount I have to pay etc. as expected. But it turns out that Discovery takes the full amount of the phone off your credit card as a once-off purchase (which by the way does not appear on one's credit card statement as a purchase). I have effectively paid cash for the phone and am now R20k out of pocket. I did not want to spend this money on a phone upfront and if I had known this is what they were doing, I would not have opted for it. I feel that the deal was ********* and underhanded and definitely not explained with any degree of clarity beforehand.