问为什么当当前的健康值为0时，我的游戏屏幕上没有显示？

EN

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
using UnityEngine.InputSystem;

public class HealthSystem : MonoBehaviour
{
    public int maxHealth = 100;
    public int currentHealth;

    public HealthBar healthBar;
    public GameObject gameOver;

    public bool damage;

    // Start is called before the first frame update
    void Start()
    {
        currentHealth = maxHealth;
        healthBar.SetMaxHealth(maxHealth);
    }

    void TakeDamage(int damage)
    {
        currentHealth -= damage;

        healthBar.SetHealth(currentHealth);
    }
    
    public void GameOver()
    {
        if (currentHealth == 0)
        {
            gameOver.SetActive(true);
        }
    }

    public void RestartButton()
    {
        SceneManager.LoadScene("Playground");
    }
    
    public void OnDamage(InputValue value)
    {
        DamageInput(value.isPressed);
        TakeDamage(10);
    }

    public void DamageInput(bool newDamageState)
    {
        damage = newDamageState;
    }
}