As you can see, ceiling is darker than other walls.
jjg
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Hi
Here few important settings and/or steps to do.
First try in Skylight Southern Hemisphere is solid - disable/enable - check how it works. Also in Skylight you can set how strong effect is.
Another step is rebuild lighting - you can have dynamic only or static lighting of some kind of mix and it can look different.
For natural ceiling look can be important overall scene quality, how many light bounces, and few other variables.
Here is A new, community-hosted Unreal Engine Wiki - Announcements - Unreal Engine Forums - start from this place.
And here maybe more usable for you guide Lighting Quick Start Guide | Unreal Engine Documentation
Anyway, ceiling light effect is not easy to do for natural look, because light need a lot of bounces and it depending on material too.