Ok, now I moved the "web" middleware from admin routes group, it seems to work, but now something strange is happening, wome routes do not work..., I am not sure if I am using middleware in the correct way...
I have
Route::get('login',['middleware' => ['web'],'as'=>'auth.getLogin','uses'=> 'Auth\AuthController@getLogin']);
Route::post('login',['middleware' => ['web'],'as'=>'auth.postLogin','uses'=> 'Auth\AuthController@postLogin']);
Route::get('logout', ['middleware' => ['web'],'prefix'=>'admin','as' => 'auth.logout', 'uses' => 'Auth\AuthController@getLogout']);
Route::group(['middleware' => ['web','auth'],'prefix'=>'admin','namespace'=>'Admin'], function () {
});