Defective 2nd hand product

<p>I bought a CPO Apple IPhone from Takealot and since I received it the screen freezes. It's been send back twice now and their returns department cannot find anything wrong. I have 2 videos to show that the screen freezes and offered to send them to Takealot to see. But no, they prefer not to satisfy customers after taking their money and providing them with a defective product</p>