Scene color doesn't work in my project

In my project at some moment stop working post process property scene color (And film also). I can create new level and use post process volume there, but there’s no effect either.
But when I create a new project and create the volume there, everything works fine. What it might be?

How can I change scene color in my project? I need to make underwater scene and I dont know how to do it without a postprocess…

Sorry, I wasnt right. I tried to change scene color in my old projects and it was successful. But if I try to change scene color in a new project, I can’t do it. Why is it going on??