Able to list web elements but not able to click it or send keys using driver.findElement


I am trying to simply login to webpage using appium and java.
My code is like this

List ls = dr.findElements(By.className(“android.widget.EditText”));
for(WebElement e :ls)
System.out.println(e.getText()); //able to get all elements like (Password,Email )

	dr.findElement((By.xpath("//android.widget.EditText[@content-desc='Password']"))).sendkeys("password testing");                                                             //But here not able to find element.

please let me know whats wrong with this code.