Hello, people!
I`ve just implemented an aiming animation, so I and AI chars can look up and down.
I placed an AI Char downstairs, and when I approach him(I’m upstairs) in spot radius the enemy turns to my and starts nodding(constantly looking up and down) and the enemy doesn`t shoot or move, looks like he wants to become a friend 
When I approach him and literally touch him, my fellow starts to shoot at me and if I return at starting position(upstairs) he is still standing on the same place, but looking at me(properly) and shooting despite the previous friendly bug.
Reloading the level didn`t help.