Exponential Fog not Showing In Player

I have Exponential Fog in my scene. It shows in the editor and in Game View. BUT, it goes away when I push play. So it is not showing in the player camera. Can anyone tell me how to fix this? I have attached screen shots below. You can clearly see the fog in the Editor. But as soon as I push play, it disappears.

Do you have any post processing effects turned on? If so, disable post processing to make sure something isn’t just filtering it out by chance.

I’m not certain if this could have any effect, but maybe check to make sure your engine scalability settings are on high\epic