Codeigniter sessions, display user's firstname - codeigniter

Question

I'm trying to display the user's firstname after login but it doesn't appear on the page. I tried to display it like this
<h2> Welcome <?php echo $this->session->userdata('firstname'); ?> </h2>
but it didn't display the user's firstname, even though there are data in DB. But when I tried to change the 'firstname' into 'username', it displayed the email of the user(test#gmail.com). How can I display the user firstname? Here's my controller:
function login(){
$this->form_validation->set_rules('username', 'Username', 'required|valid_email');
$this->form_validation->set_rules('password', 'Password', 'required');
if ($this->form_validation->run() == FALSE) {
redirect('/');
} else {
$user_login = array(
'username' => $this->input->post('username'),
'password' => $this->input->post('password'),
);
$login = new UI_model;
$result = $login->login_user($user_login);
if($result){
$auth_details = array(
'firstname' => $result->firstname,
'lastname' => $result->lastname,
'username' => $result->username,
);
$this->session->set_userdata($auth_details);
// $this->session->set_userdata('authenticated', '1');
$this->session->set_flashdata('status', 'User Logged in Successfully!');
redirect(base_url('pages/index'));
} else {
$this->session->set_flashdata('status', 'Invalid Credentials. Please try again');
redirect(base_url('pages/about'));
}
}
}
Here's my Model:
public function login_user($data){
$this->db->select('*');
$this->db->where('username', $data['username']);
$this->db->where('password', $data['password']);
$this->db->from('users');
$this->db->limit(1);
$query = $this->db->get();
if($query->num_rows() == 1){
return $query->row();
} else {
return false;
}
}

Answer 1

Can you attach an image of your database you are using for and echo all data session?