Pixel Animated GIFs Break

When I upload animated Pixel Art GIFs to Discord that I made, there always seems to be weird blue, yellow, or red unwanted lines around the objects in my animation. Why is this, and can it be fixed? (Also, my GIFs are 92x92 resized to 920x920 and posted with a .gif file. Another detail is that they're made in Piskel, but I doubt that the application will matter.)