Why the small mesh in the scene has incorrect light effect?

Hello,everyone,I met a very urgent problem. I got a small mesh as a light switch in the room.When I stay far away from the mesh,the mesh is very bright that caused by the direction light in the scene.But when I move close to the mesh,the mesh will be black,I don’t know why,So pls help me!!
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I met the problem,too.pls help us,thanks a lot.

what is the light source setting you are using? static, stationary or movable?
Set your lights to movable and rebuild to see what happens there

Hello.The light source is stationary directional light.Because most meshes in my scene are static meshes.So I think it’s not necessery to use moveable type.It’ll be very expensive to the performance