Issue with black sky

I have an issue with the black sky when I go to places like Japan. It was completely black before I changed Transmittance Min Light Elevation Angle and now only the sky is black. What could be the issue here?

Just to check the simple stuff first, have you tried changing the “Solar Time” property on the CesiumSunSky? If it’s not that, can you please give us detailed instructions about you’ve done, preferably starting with the Cesium for Unreal Samples project, so that we can reproduce the problem?