Faint, weightless lines appearing on the edge of overlapping shapes

These faint lines keep appearing when I create overlapping shapes, as can be seen at the very bottom and top of the image. It should be completely white like the sides. They change slightly when I zoom in/out. The paths are completely lined up and the only stroke is on the inside of the path. I don't know how to get rid/not see them. Is this a bug? I can fix it by making my shapes slightly smaller although it seems like there should be a better way. Running Adobe Illustrator CC 2018, GPU Preview. Any help would be appreciated!!
