Radio silence after product return

I recently bought a laptop on Takealot. When I received the laptop I tried to turn it on, everytime I try and connect to the internet, the laptop freezes and restarts. I returned the laptop for replacement, as it was a gift for my son. I returned the product on 17 December, thinking it will be replaced by the 23rd or 24th. I havent received an update of as yet, and I have contacted the help centre numerous times. but still i have no feedback. i had also requested to not replace the item but rather refund me as i have seen another laptop that my son wants on takealot. nothing. radio silence. I think it is rather unprofessional that I have to beg for updates. and still I am in the dark. How must I face my son knowing that I dont have a Christmas present. I am very unsatisfied with takealot and i really hope they do something about it.