I am getting this.driver” is null , Would you be able to help and what should be fixed?

java.lang.NullPointerException: Cannot invoke “org.openqa.selenium.WebDriver.quit()” because “this.driver” is null
at hooks.MyHook.teardown(MyHook.java:24)

public class MyHook extends Base{   
        @Before
        public void beforeScenario(){
        System.out.println("Scenarios has started");
        }
        @After
        public void teardown()  {
        driver.quit();
        }   
}

public class Base {
    public WebDriver driver;
    public Properties prop;
    
    public WebDriver initializeDriver() throws IOException{
    prop= new Properties();
    FileInputStream fis=new FileInputStream("C:\Users\CITPL-Developer-2\eclipse-workspace\Fdms\src\main\java\citpl\resources\data.properties");
    prop.load(fis);
    
    String browserName = System.getProperty("browser")!=null ? System.getProperty("browser") :prop.getProperty("browser");
    
    if(browserName.equals("chrome"))
    {
        ChromeOptions options = new ChromeOptions();
        options.addArguments("--remote-allow-origins=*");
        System.setProperty("webdriver.chrome.driver","C:\Users\CITPL-Developer-2\driver\chromedriver.exe");

        if(browserName.contains("headless")){
        options.addArguments("headless");
        }       
        driver = new ChromeDriver(options);
        driver.manage().window().maximize();
    }
    driver.manage().timeouts().implicitlyWait(Duration.ofSeconds(10));
    return driver;
    }

public class LoginSteps extends Base{

    @Given ("Naviagate to the login page")
    public void Naviagate_to_the_login_page() throws IOException {
        initializeDriver();
        driver.get(prop.getProperty("url"));
    }
    @When ("^I enter valid username (.+) and password (.+)$")
    public void I_enter_valid_username_valid_username_and_Pasword(String username, String password) throws InterruptedException {
        LoginPage lp= new LoginPage(driver);
        lp.entervalidCredentials(username, password);
    }

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