Core Incompetence Favours Their Bottom Line

My 2018 MacBook Pro 13" (with touch bar) (still under warranty) has a problem with a flickering screen - a bar of red noise that appears in the lower half of the screen every few seconds. The screen flickers intermittently, but regularly enough that I am unable to work on the laptop.

Core Group has had the laptop twice now, for a total of 6 weeks! Each time they claim that their technician is unable to reproduce the problem, and then they send the laptop back.

However, the problem is bad enough that the laptop is pretty much a R35k paperweight now. I am basically having to pay this small fortune because of the incompetence of Core technicians, incompetence that I should mention acts in the interest of Core.