Paying for Goods under warranty.

On the 1st of May I went to into MTN lakeside for an upgrade, the consultant took my phone out of the box and accidentally dropped my phone i told her to go get a new one and she told me if the phone gives me problems within 7 days I can just bring if in, unfortunately problems started arising last week when my phone made a loud noise out of the blue, I had kept the removable plastic on the phone but it also started peeling itself and that's when I noticed a tent I took the phone in today and they accept me to pay R330.00 for the assessment, then only will I receive a quote in which I will also have to pay for repairs done the phone is only two months old, The after sales service at MTN really sucks I wanted to terminate my contract with them with immediate effect and they told me to phone they call center, I mean I am in store already why call the call center, I am totally unhappy with they service and would never recommend it to anyone. For the most expensive network they run a horrible after sales service the call center takes up to 45 mins to answer one call...