Cinematic DoF preview + DoF layers doesn't show up in editor

Hey All!
I’ve watched a lot of documentation on cinematic cameras and DoF in 4.20 and above. i’m on 4.21.
according to all the tutorials, i should be able to just pilot my cinematic camera, and by default preview the DoF in real time, and I should also be able to visualize the DoF layers in real time.
for some crazy reason I can’t see either of these and it makes my work really difficult because its a bunch of guess work.
I can still use the debug plane, but that is not a great reflection of what the final render is.
Has anyone had this issue? Is there something I need to turn on or off that i’m missing?
plz halp.