Strange illuminance level in each floor and windows


I am conducting daylight analysis, and I want to have illuminance level for the second and third floors of my model. As you can see in the first picture, the illuminance level of the second and the third floors are different while the windows of the both floors are exactly the same.

So I decided to see what happens in the illuminance level in windows surfaces of the whole building. The second picture shows that the illuminance level of the windows of each of the facades are different in each floor, which it is really strange for me.

I attach the file here.
Helia For (763.8 KB)
Would you please help me to solve it? (also the legend of all of the windows and the floors are from 0 - 500 lux).
Thanks for your consideration.
Best Regards,