artifacts in my car model

I am working on a car and it has some little artifacts. does anyone knows how to fix them. You can see them on the side of the car at the door. And what do you think of the car it also has doors and a spoiler but these are separate objects :evilgrin:


Have you tried putting an edge-split modifier on it?

yes but it doesn’t work
i think because i made the mistake i did subdivide but that is not good
next time i use just the knife tool