rotation – Unity: transform.LookAt (target) does not "look" at the target?

It's been several hours since I repair a prefabricated and I have more ideas. It is a method with which I thought to be comfortable, transform.LookAt (target). I have this prefab:

enter the description of the image here

As you can see, I checked that the eye registration points were in the center of the mass; I've also verified that they were spinning correctly for the X, Y and Z axes. The yellow ball you see is the target object and NOT NOW inside the prefabricated.

I've tried two ways to get the eyes to look at the target. The first is this script, which caused a 90-degree eye-stroke in the counter-clockwise direction around the y-axis (which is very false). I applied this script to both eyes. Check it out:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class LookAt : MonoBehaviour
{
    public Transform target = null;

    // Update is called once per frame
    void Update()
    {
        transform.LookAt(target);            
    }
}

And please, before thinking it: Yes, I remembered to set the target object in the editor. You can see the eyes pointing to the side instead of the target:

enter the description of the image here

I found this other script on the Unity documentation that was not working at first, but then I replaced "Rotation" with "LocalRotation", since I was near, inverted the vector "RelativePos" ", and it worked – but only on the y-axis:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class LookAt : MonoBehaviour
{
    public Transform target = null;

    // Update is called once per frame
    void Update()
    {
        Vector3 relativePos = transform.position - target.position;

        // the second argument, upwards, defaults to Vector3.up
        Quaternion rotation = Quaternion.LookRotation(relativePos, Vector3.up;
        transform.localRotation = rotation;

    }
}

You can see here that it works in the XY plane at eye level, but take my word when I say that the eyes can not look up or down if I move the ball up and down:

enter the description of the image here

How can I solve this problem so that the eyes always look at the target I need?
Thank you sincerely for your time.