Missing Lighmass in Importance Volume

Hello everyone,
I have an issue with Lightmass. I have all around the room set up a Lightmass Importance Volume. But some Areas are covered with Lightmass Samples in a high density. But a big area are not covered.
I tried already to use the Density Volume. 
I tried to split up in smaller volumes. 
But nothing have helped. It’s always the same area that is not covered, and my character loses all Shadow from the surrounding in that area.
Does someone know what’s happening here?

Here you see the Importance Volume

Presumably, your character is moving? Then it will only use moveable lighting anyway.

No, moveable objects use this data to create shadows on the mesh. You see a huge difference if you use it or not.

My bad…

My Solution:
“We should take Bikini Bottom and push it somewhere else!” - Patrick Star

I just moved the room to another location, and it worked fine. 
Took me some months to get the idea.