Locker system

This is the code I have right now to get a locker system. If a button is pressed, currentCat is incremented, and i want the next cat to show, and the previous one to hide, but its not working

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

public class LockerManager : MonoBehaviour
{
public GameObject Cats;

private int currentCat = 0; 

public void NextCat()
{
    currentCat += 1;
}
public void PreviousCat()
{
    currentCat -= 1;
}
private void Update()
{
    print(currentCat);
    getCat();
    if (currentCat > Cats.Length)
    {
        currentCat = 0;
    }
    if(currentCat < 0)
    {
        currentCat = Cats.Length;
    }
}
void getCat()
{
    for(int i = 0; i <  Cats.Length; i++)
    {
        Cats*.SetActive(true);*

}
for (int i = 0; i > Cats.Length; i–)
{
Cats*.SetActive(false);*
}
}
}

public class LockerManager : MonoBehaviour
{
public GameObject Cats;
private int currentCatIndex = 0;

    public void SelectCat( int index )
    {
        if( index < 0 || index >= Cats.Length )
            return ;

        Cats[currentCatIndex].SetActive( false );
        currentCatIndex = index;
        Cats[currentCatIndex].SetActive( true );
    }

    public void NextCat()
    {
        SelectCat( (currentCatIndex + 1) % Cats.Length );
    }

    public void PreviousCat()
    {
        SelectCat( (currentCatIndex - 1 + Cats.Length) % Cats.Length );
    }
}