Payjoy ****med me legally

I "bought" a phone for my son today using Payjoy. When reviewing the contract I noticed that it is a lease agreement and not a credit agreement. Furthermore clause 18 states that at the end of the agreement I must buy the phone from Payjoy at a market related or return it to them. This was not how I understood it and this clause was never explained to me by the salesperson at Incredible Connection. So for a phone that costs R2799 I am going to pay more than R6000 rand during the 9 months payment period, and then I still have to buy it from Payjoy. I have been misled, I think this is a legal ****. Also, the advertising is misleading, making it sound like a credit agreement when it is actually a lease/rental agreement.