title: The request is missing a required parameter, includes an invalid parameter value, includes a parameter more than once, or is otherwise malformed
body: <p>I am developing an auth api with laravel, passport and postman. I have seen related post but none of them solved my problem. If I try to send a request it shows me this error. I have tried all I can but it just displays this error</p>
  
  <pre><code>{
  "error": "invalid_request",
  "message": "The request is missing a required parameter, includes an invalid parameter value, includes a parameter more than once, or is otherwise malformed.",
  "hint": "Check the `username` parameter"
  }
  </code></pre>
  
  <p>my value for the application is </p>
  
  <pre><code>{
  "grant_type" : "password",
  "client_id" : "2",
  "client_secret" : "fsDFrzGtmpMjoxWtplnvcmgKT3USzKFfKQu6alGF",
  "email":"john@gmail.com",
  "pssword" : "12345",
  "scope" : "*"
  }
  </code></pre>
  
  <p>api.php</p>
  
  <pre><code>&lt;?php
   use Illuminate\Http\Request;
   Route::middleware('auth:api')-&gt;get('/user', function (Request $request) {
  return $request-&gt;user();
  });
  Route::post('signup', 'SignUp@signUp');
  </code></pre>
  
  <p>auth.php</p>
  
  <pre><code>'guards' =&gt; [
      'web' =&gt; [
          'driver' =&gt; 'session',
          'provider' =&gt; 'users',
      ],
  
      'api' =&gt; [
          'driver' =&gt; 'passport',
          'provider' =&gt; 'users',
      ],
  
  
  'providers' =&gt; [
      'users' =&gt; [
          'driver' =&gt; 'eloquent',
          'model' =&gt; App\User::class,
      ],
  </code></pre>
  
  <p>User.php</p>
  
  <pre><code>class User extends Authenticatable
    {
  use Notifiable;
  
  /**
   * The attributes that are mass assignable.
   *
   * @var array
   */
  protected $fillable = [
      'name', 'email', 'password','vCode',
  ];
  
  /**
   * The attributes that should be hidden for arrays.
   *
   * @var array
   */
  protected $hidden = [
      'password', 'remember_token',
  ];
  </code></pre>
  
  <p>AuthServiceProvider.php
          
  
  <pre><code>namespace App\Providers;
  
  use Laravel\Passport\Passport;
  use Illuminate\Support\Facades\Gate;
  use Illuminate\Foundation\Support\Providers\AuthServiceProvider as ServiceProvider;
  
    class AuthServiceProvider extends ServiceProvider
  {
      /**
       * The policy mappings for the application.
       *
       * @var array
       */
      protected $policies = [
          'App\Model' =&gt; 'App\Policies\ModelPolicy',
      ];
  
      /**
       * Register any authentication / authorization services.
       *
       * @return void
       */
      public function boot()
      {
          $this-&gt;registerPolicies();
  
          //
          Passport::routes();
      }
  }
  </code></pre>
  
  <p>Please any solution will be really appreciated</p>