When I was testing my game, I found that when I looked down, a shadow suddenly appeared. I had a little look around, and discovered that the shadows also appear in the editor when you look down. I have looked around, and decided to turn the shadow type from the Directional Light to No Shadows. That got rid of the shadow when you look down, but I do want shadows in my game. If anyone has an answer, suggestion, or link to another topic, feel free to post.
You can turn off cast and receive shadows in the objects renderer. That should fix it for you.