Hi, when you set up lighting for my rig, you might jump into this issue: eyes are rendering black.
You can go to Window > Outliner
If this green arrow appears, turn it off (This is Outliner’s filter)
Find something is called “lens” or “eye cells”
You can simply hit Ctrl + H to hide them. Or add to layer and hide them.
Or you can assign water-like or glass-like shaders to them. It’s is different from renderer to renderer but the general rule is max out Refraction and zero out diffuse weight (or you can use preset if your renderer provides one):