Auth login throttling not working in Laravel 5.2 in default auth

In routes.php

Route::post('/login', ['uses'=> 'Auth\AuthController@postLogin']);

In my AuthController

use Illuminate\Foundation\Auth\ThrottlesLogins;
use Illuminate\Foundation\Auth\AuthenticatesAndRegistersUsers;

class AuthUserController extends Controller
{
    use AuthenticatesAndRegistersUsers, ThrottlesLogins;
-------
    protected $maxLoginAttempts = 4;
    protected $lockoutTime = 300;

and thats it I am not overriding the post login just letting it use the default.

So, after trying more than 4 times also it's not throttling the request i.e. no error resonses for throttling. Please help.

via Chebli Mohamed