Material probems!

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1

Hi there! I dont know why the lighting of my model not working properly both in the render & in the preview . I tried to reimport it, use the other properly working duplicates but it still not working. These vertical aluminum boards are the very same instances.

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image1825×1134 422 KB

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image2016×1220 777 KB

And it only happens to the 2nd level of the building

2

Hello, what modeling software is the model come from? Please check whether the faces of those parts are reversed. You can try “reversing faces” of them, then sync again or re-import the model.