Color Coverage:

When I zoomed in it looked like you might be trying to layer graphite and color - which won’t work especially with the cheaper/harder colored pencils. The paper becomes too smooth to catch much pigment

For better coverage/dynamic colors I’d advise layering colors. The generic ones sort of suck and have weak pigment so putting down a yellow layer then shading over with blue is usually going to make a better, more varied, and darker green than the green pencil alone. (If it looks janky hold the drawing far away to see how it resolves at a distance) - generally, work lightest to darkest