Terrible Terrain Lighting

Just a quick question. How do I fix the terrain lightning? On my game, I could even add its own sunlight just to glow into that shadow, boost the ambient to max/turn it off, and even turn off all reflections.

(I also played around with smoothness and metallic properties)

The terrain shadow WILL NOT go away, and it follows me. When I try spotlights, sometimes my light even poofs into thin air. I can find scatters and pieces of it, and someone told me to add mountains, but what if I wanted a flat terrain. On my two other games, this isn’t an issue, and I don’t know what I did.

I’d appreciate help alot!

As you can see, there is even a sun shining into that shadow, yet not even that fixes it.

Nevermind. You just make it Legacy Diffuse… They should atleast try to fix it…