How can I display specific data from a MySQL database? (fetching user's email)

I have made a registration system with a my account page.

I can display name and password in it but cannot display email after login because I have to fetch it from MySQL database as the user doesn't enter his email at login.

No error in code but email not displayed.

This is server.php login code:

// LOGIN USER 
if (isset($_POST['login_user'])) {
  $username = mysqli_real_escape_string($db, $_POST['username']);
  $password = mysqli_real_escape_string($db, $_POST['password']);

  if (empty($username)) {
   array_push($errors, "Username is required");
  }
  if (empty($password)) {
    array_push($errors, "Password is required");
  }

  if (count($errors) == 0) {
    $password = base64_encode($password);
    $query = "SELECT * FROM users WHERE username='$username' AND password='$password'";
    $results = mysqli_query($db, $query);
    if (mysqli_num_rows($results) == 1) {
      $_SESSION['username'] = $username;

//Here is the code with problem

      $query = "SELECT email FROM users WHERE username='$username' AND password=''$password";

      $result = mysqli_query($conn, $sql);

    if (mysqli_num_rows($result) > 0) {
    while($row = mysqli_fetch_assoc($result)) {
        $_SESSION['email'] = $row["email"];
    }
    }

//Here it ends

      $_SESSION['password'] = $password;
      $_SESSION['success'] = "You are now logged in";
      if ($_SESSION['page'] == "account.php"){
          header('location: account.php');
      }
      else{
        header('location: index.php');
      }
    }else {
        array_push($errors, "Wrong username/password combination");
   }
  }
}