ION_AUTH :: $this->ion_auth->logged_in() giving me bool-false in MY_Controller

Question

I have been using code igniter and ion_auth for authentication.

My Directory structure is as given below,

Project
  - application
      -config
   - modules
      -admin 
       -config
       -controller 
           **-Login.php**

   - core
      - controllers
         - Admin Controller
      - MY_Controller

Login.php is having below line of code,

$this->ion_auth->login($identity, $password, $remember) 

above is working.

But after that in other file there is one call for checking logged in user as given below,

   $this->ion_auth->logged_in()

Above line is not working and if I print var_dump then it shows me bool(false)