How do I fix these shadows?

This is probably a beginner question, but how do I fix these weird blob-like shadows?

I started a new project with starter content and then made a new default level. Then I scaled the floor by 10 on the X and Y axes, and made this structure out of the starter content architecture. I set the influence radius of the sphere reflection capture to 6,000. Then I build the lighting and the shadows got weird.

Hi!

It’s due to low resolution lightmap on the receiver surface (floor).

Thanks! It worked!

I was wondering if it had any significant impact on performance, or does it only increase the build times?

Dynamic movable lighting yes. Bake static lighting no. Bake lighting will increase build time but is free

Thanks!

There is a VRAM cost too, so dont increase everything to max for no reason.