[increase cura buildplate limet]

Im new here so if i did anything wrong please tell me.

 

 

So im trying to print this peace on my ender 3 and is should fit on the build plate, but i cant slice it because of the gray areas on the left and right.

I tried slicing it in creality slicer and it worked. Only the print qualty of cura is better so id rader use cura,

 

I was wondering does anyone know how to remove/make the gray boxes on the side smaller?

 

I already tried to make the build plate bigger in cura but the boxes stay.

Also have removed skirts.

And tried changing some support setting but those things do not help.