Method App\Http\Controllers\NewsController::isDeferred does not exist.

I'm new in laravel. I appreciate your help guys. trying to build a json API for backend of a newsdashboard with laravel. made migrations. I created the routes. made models. made the controller. Now I'm getting this error whenever I want to serve:

Method App\Http\Controllers\NewsController::isDeferred does not exist.

Here is my code guys:

Here are my routes:

use Illuminate\Support\Facades\Route;
use App\NewsItem;
use App\Http\Controllers\NewsController;



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

Route::get('/news', 'App\Http\Controllers\NewsController@index')->name('news.index');
Route::get('/news/{newsItem}', 'App\Http\Controllers\NewsController@show')->name('news.show');
Route::post('/news', 'App\Http\Controllers\NewsController@store')->name('news.store');
Route::patch('/news/{newsItem}', 'App\Http\Controllers\NewsController@update')->name('news.update');
Route::delete('/news/{newsItem}', 'App\Http\Controllers\NewsController@destroy')->name('news.destroy');
Route::get('/news/create', 'App\Http\Controllers\NewsController@create')->name('news.create');
Route::get('/news/{newsItem}/edit', 'App\Http\Controllers\NewsController@edit')->name('news.edit');

Here is the controller that was mentioned in the routes:

<?php

namespace App\Http\Controllers;

use App\Category;
use App\NewsItem;
use App\Tag;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Validator;

class NewsController extends Controller
{

    /**
     * Display a listing of the news items.
     *
     * @return \Illuminate\Http\Response
     */
    public function index()
    {
        $newsItems = NewsItem::with('category', 'tags')->get();

        return response()->json($newsItems);
    }



// and the rest of the code which are rest of the CRUD functions... and some validations


}

Here is NewsItem mode:

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class NewsItem extends Model
{


    // Specify the table name for the model
    protected $table = 'news_items';

    // Specify the fillable fields for the model
    protected $fillable = [
        'title',
        'body',
        'category_id',
        'url',
    ];

    // Define the relationships for the model
    public function category()
    {
        return $this->belongsTo(Category::class);
    }

    public function tags()
    {
        return $this->belongsToMany(Tag::class);
    }
}

And made two other similar models for Tag and Category too.

Before getting this error I got another error : Class "App\NewsItem" not found

and then I added my controller and model classes to the $providers array in the config/app.php file and now I'm getting this error in the title.

I tried: composer dump-autoload and I'm getting :

Class App\Category located in D:/news-dashboard/app\Models\Category.php does not comply with psr-4 autoloading standard. Skipping.
Class App\NewsItem located in D:/news-dashboard/app\Models\NewsItem.php does not comply with psr-4 autoloading standard. Skipping.
Class App\Tag located in D:/news-dashboard/app\Models\Tag.php does not comply with psr-4 autoloading standard. Skipping.
> Illuminate\Foundation\ComposerScripts::postAutoloadDump
> @php artisan package:discover --ansi

In Controller.php line 68:

  Method App\Http\Controllers\NewsController::isDeferred does not exist.


Script @php artisan package:discover --ansi handling the post-autoload-dump event returned with error code 1