item bought in a month and exchange refused

I purchased a brand new twisp edge on the 17.05.15. The item was used to date and the inner glass on both units began to crack. I took the units back to the twisp kiosk at the liberty Midlands mall where I made the purchase and they refused to exchange both...saying it was dropped because it has scratches on it...surely the units will be dented and not scratched... ? This is unbelievable as I having making purchases from them on a monthly basis for over 2 years. I'm shocked with the level of service and will most certainly take this to the consumer council should my problem not be rectified.