It’s not normal map related, it’s based on the mesh topology with dynamic shadows. If you’re baking lighting or using WholeSceneDynamicShadows it shouldn’t be visible(until you start reducing shadow bias, which then you’d introduce shadow acne/banding and notice the geo in some cases). But with Cascaded Shadow Maps, it’s more prominent. You can alleviate it by tweaking the standard bias and sharpness settings for the shadows, adjusting the cascaded shadow map distribution depending on where it occurs, or if performance doesn’t matter, you can reduce the issue by enabling a per-object shadow map for the mesh by checking the “Dynamic Inset Shadow” on the mesh. You can also increase the subdivisions in your modeling package or with PN Triangles and tessellation in the material. 