Selenium WebDriber not working fine on Amazon site : 
I am trying to write a Selenium test against Amazon site. I want to get "Sign in" element so that I can click on it.

url: www.amazon.es

Here is my Selenium Code:

System.setProperty("webdriver.gecko.driver","C:\\geckodriver-v0.18.0-win64\\geckodriver.exe");

		WebDriver driver = new FirefoxDriver();
		driver.get("https://www.amazon.es");
	
		
		try{
			
			driver.findElement(By.id("nav-link-yourAccount")).click();
			
		}catch (Exception e){
			System.out.println("Not Found");
		
			}

Sometimes the code works correctly but sometimes it does not find the ID "nav-link-yourAccount".
 What is the problem? and how can I solve it?

Thank you