Changing of settings in runtime with different effect

Hallo everyone,

I am building a virtual environment that can change the settings in runtime. I am using the Sun Positioning plugin, to allow the user to change the location dynamically. It works fine, except for night times, the scene is not really dark. I found out this is a common problem and can be solved by changing the sky sphere and directional light color.

When I do that before pressing play in the editor this works perfectly fine and the scene is dark. However, when I change the same settings in the same order in runtime with my widgets, then the scene is still not totally dark. So I assume some additional step is required in runtime that simulates basically the same when I press the play button in the editor.

Scene, when settings changed before:

Scene, changing same settings in runtime:

I would really appreciate any help!

Kind regards