Honeybee daylight simulation - light passing through wall

Hi 

I am trying to use Honeybee to do a simple daylight simulation of a building

I encounter with the problem that the illuminance is high just beside an opaque wall, ie the light passed through the wall for an area

I have checked the model the wall is well touched with the roof and ceilings and floor.

Does anyone have any idea what is wrong?

Thanks!

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