Multiple Problems with Lighting

Hi, I am experiencing multiple problems with my game where the lighting looks bad. It is still the same after I have built the lighting in Preview mode and in Production mode. I have a skybox, a SkyLight, a PostProcessVolume, a LightmassImportanceVolume and an ExponentialHeightFog and they all have normal settings with nothing out of the ordinary.
Firstly, the shadows seem to be much better for fences before I build the lighting. Here’s the shadow before and after I built lighting:

And then there is a problem with the tree shadows. You can see before I built the lighting it looked fine and then it looked terrible.

There is also a problem with shadows with the roads. They are split up into modular pieces and where the road pieces connect, the shadows seem to weirdly split up and the shadows don’t connect properly with the other side. Here:
I also have a problem with lighting on landscapes because they seem to get completely random shadows out of nowhere on the edges and in the land. (this land is completely flat):