Refund or exchange of laptop

On 23 November 2018 ( Black Friday) I purchased a new Acer laptop at Makro Springfield, and the laptop was returned on 27 February 2019 because the laptop kept freezing on the Acer logo.

At Makro I was notified that, I cannot get a refund, nor exchange the laptop, because Makro's terms and conditions state that the unit needs to be taken in for repairs, so the unit was taken in and returned on March 15 2019. Acer digital planet in Midrand replaced the motherboard.

On April 08 2019, the laptop is back to square one, still freezing on the Acer logo. I cannot be having the same problem every three weeks because this laptop is used for my son's IT course in university.

I would like to exchange the product, because my six months with the product is not over yet. Honestly I am fed up with the brand.