Material getting darker closer to ceiling

Hey guys.
In the example scene below, the material on my object starts to get darker as it gets closer to the ceiling, even with a direct light closer to it. On the second image, the same object with the same material is “lit as it should” (using only Movable Lights, no Skylight). On the third image, the same object with another material is ok as well.What might be the problem? 4th image is the faulty material.
Thanks in advance.

P.S. Don’t want to use skylight

P.P.S. Can’t use static/stationary lights (movable only)