Defective products three times in a row

I purchased a Proline Powerbank from Takealot last year thinking that it was a good buy. I started to use the powerbank in January and just after a mere 2 uses it stopped charging my mobile. It came on for a few seconds and went off no matter how much the actual powerbank was charged. I gave the product the benefit of the doubt as technology has its defects. I requested that Takealot fetch the powerbank and inspect it. They gladly did not and the supplier identified that it was faulty and sent through a new one. Bear in mind that this process takes no less than 3 weeks from pick up to delivery. I then started to use the new unit and shortly after that the unit refused to charge no matter what cable I used. Quite frustrated once again I requested that Takealot come fetch the unit again and inspect it. The supplier once again identified a fault and replaced it with a new one. As frustrated as I was, I accepted the new unit thinking that I would not have this problem again... And what do you know, it happened yet again. So the same product gets sent back THREE times due to faults and Takealot insists that I take the same product for the FOURTH time due to their policies etc. This is unacceptable as Takealot itself does not stock this product any longer. I begin to question why they don't. I merely wanted a refund for the purchase value so that I can purchase a reliable powerbank from the Takealot website. With that being said, the consultant insisted that they want to send me the new unit so I gladly told them that they can keep that piece of **** and I WILL NOT be purchasing anything from them ever again. I will also spread the word to family and friends about the incompetence and inconvenience of this transaction.