What's wrong with this shadow?

I have trouble with lighting and shadows. I don’t know why i have some black lines on my components or why nice looking shadows become a blurry and bad looking after build light. I hope someone can help me with that or tell me what i’m doing wrong. I’m adding some photos of this problem.

P1 one floor is dark and second is light

P2 how it look before build light

P3 also how it look before build light
Imgur: The magic of the Internet (after is very blurry)

P4 and how it look after build light

First of all - chek lightmaps uv on meshes (P1)
Lightmap resolution is small (P2,3,4) - try to increase it

I try to increase it but actually nothing really change. I’m not sure what about light building, when i increase it and build light in preview it reset to same bad look and also when i do that on production build nothing change. Here are photos with floor lightmaps uv configuration: