Dell 9570 xps15 4k oled display dark spot problem

Hello guys, 

   I purchased this xps 15 9570 4k oled display recently directly from the Dell store. When i was purchased i identified the issue on the display having vertical dark grids. I raised a complaint against the issue and the technical support replaced with the new one which took long time to get replaced. And the thing is when i got the new one again i got the same issue appeared on the screen which is dark spot on the screen and  i raised the issue tech support saying that could be because of lcd problem. This issue is really so weird and annoying while working. This is my 2 years dream to get xps laptop in my hands at last its totally disappointed me and it didnt reach expectations. This is not that cheaper to neglect the issue. Please help us to get rid of this display issues and to be honest dell performance is beast than other laptop. There is no comprise in the performance but the only problem is about the screen. I hoping on the Dell team to get resolve this issue soon.