Laravel problems to redirect after authenticating?

I'm starting to learn how to use Framework Laravel and I'm having a problem with the targeting after login, I'm using the Framework own login system.

To learn how to use Framework I am creating a simple blog and at the time of logging in this is directing to the path /admin same as changing the protected $redirectTo = '/dashboard' attribute

I would like to know what can be because I could not find the bug ?

As requested by the friends below, follow the code of the routes and class where I changed the redirectTo attribute.

routes / web.php

<?php
    Route::get('/', function () {
        return view('welcome');
    });

    Auth::routes();
    Route::get('/admin', 'HomeController@index');

    Route::group(['prefix' => 'dashboard'], function() {
        Route::get('/','DashboardController@index');
    });

app \ Http \ Controllers \ Auth \ LoginController.php

<?php

    namespace App\Http\Controllers\Auth;

    use App\Http\Controllers\Controller;
    use Illuminate\Foundation\Auth\AuthenticatesUsers;

    class LoginController extends Controller{

    use AuthenticatesUsers;

    /**
    * Where to redirect users after login.
    *
    * @var string
    */
    protected $redirectTo = '/dashboard';

    /**
    * Create a new controller instance.
    *
    * @return void
    */
    public function __construct(){
        $this->middleware('guest', ['except' => 'logout']);
    }

App / Http / Controllers / HomeController

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;

class HomeController extends Controller
{
    /**
     * Create a new controller instance.
     *
     * @return void
     */
    public function __construct()
    {
        $this->middleware('auth');
    }

    /**
     * Show the application dashboard.
     *
     * @return \Illuminate\Http\Response
     */
    public function index()
    {
        return view('home');
    }
}