Will not exchange a 2 month old cellphone

I bought a cell phone in October for R1000. The phones screen just went blank 30 December. I took the phone back and they said it must be sent in for repairs. I wanted a new one as it was not even 3 months old. I googled The Customer Protection Act and according to that is a product is less than 6 months old the customer has the right to choose between 3 options. 1 To get your money back, 2 To exchange. 3 To get repaired. I wanted to exchange for a new phone as my whole business runs via my phone. I have the original slip and the box of the phone. I spoke to the area manager and she just said it doesn't work like that. How come the Customer Protection act only counts for some. The manager of the store was very helpful and felt bad for the situation but the area manager just said I can do what I must. I am a salon owner and all appointments are made via a call or whatapp. I has been over 2 and half weeks and mtn repairs say they are waiting for parts.