Some help with shading/topology needed

Hi all. I’m trying to clean up a shape I got that I have cut out of a quad sphere. I think I managed to get it to a state where it’s mostly quads (with some triangles that I haven’t resolved yet…), however, I guess my flows are pretty bad, because the surface looks rather lumpy, and I’m also getting these artefacts in some of the corners.

Can anyone explain why that is? I thought if I have quads around the edge, it should be ok?
Would appreciate any advice! Thank you

You can try the function: Recalculate Normals.
In edit mode, press ‘A’ to select all. And then apply recalculate (shortcut: Shift + 'N)
Also make sure to activate auto smooth (Data properties / Normals / Auto smooth) if you applied shade smooth. Hope these works.

I have tried all of this, should’ve mentioned in the post, my bad. I guess I can minimize this particular artefact if I insert an edge loop and move it closer to the edge of the shape, but I still don’t know how to make the surface look smooth, it’s pretty lumpy even with 3 levels of subdiv.