[HELP] AI Perception Sight

Hi,

I’m trying to do a kind of metal gear game, so I made a military base and put some barriers crouching to hide from the patrol, I made two guards moving on a route, and testing if barriers block vision from them i got that if I stand behind the wall they can’t see me… I attach a screenshot I want that they can see my head because i think that right now they only can detect the body as a sphere

Thanks!

I’ve got this, but it didn’t work, what is wrong?