The river does not change color at night

Hello, help me please.
I created a forest with river (weather tool from the marketplace), trees, waterfall, etc … a dinamyc day / night with post process volume, but during the night the river does not change color, it remains illuminated like that of the day. I’ve already tried to rebuild the lights … but nothing. Does anyone have any suggestions? Only the river and the waterfall do not change color and lighting in the night. Thanks in advance