unexpected errors for my test

Hello,

I on my tests yet and I have unexpected errors.

............                                           23 / 23 (100%)

Time: 30.1 seconds, Memory: 30.00 MB

There was 1 failure:

1) Tests\Feature\ProjectCreationTest::the_fields_are_filled
Session has unexpected errors: 

[
    "Il semblerait que ce titre soit déjà pris",
    "The thumbnail must be an image.",
    "The material field is required.",
    "Vous devez inscrire au moins un matériel pour ce projet"
]
Failed asserting that true is false.

/var/www/html/goshr/vendor/laravel/framework/src/Illuminate/Foundation/Testing/TestResponse.php:991
/var/www/html/goshr/tests/Feature/ProjectCreationTest.php:111
/home/audrey/.composer/vendor/phpunit/phpunit/src/TextUI/Command.php:201
/home/audrey/.composer/vendor/phpunit/phpunit/src/TextUI/Command.php:160

FAILURES!
Tests: 23, Assertions: 71, Failures: 1.

But all my fields are filled

result `dump($response)`

#data: array:6 [
          "category" => 1
          "user_id" => 1
          "title" => "Ab iste esse qui fugit quas exercitationem vitae molestias."
          "thumbnail" => "891833a5f5421160f20fb75c62d07989.jpg"
          "material_id" => array:2 [
            0 => 1
            1 => 2
          ]
          "content" => "Aliquid quaerat dolorem dolorem nihil architecto eligendi. Optio autem est molestias incidunt quas illum."
        ]


#initialRules: array:7 [
          "category" => "required"
          "title" => "required|unique:projects|min:10|max:80"
          "thumbnail" => "nullable|image|max:5000"
          "material" => "required|array|min:1"
          "material.*" => "nullable|alpha_num|between:3,200|distinct"
          "material.0" => "required"
          "content" => "required|min:10"
        ]
        #rules: array:6 [
          "category" => array:1 [
            0 => "required"
          ]
          "title" => array:4 [
            0 => "required"
            1 => "unique:projects"
            2 => "min:10"
            3 => "max:80"
          ]
          "thumbnail" => array:3 [
            0 => "nullable"
            1 => "image"
            2 => "max:5000"
          ]
          "material" => array:3 [
            0 => "required"
            1 => "array"
            2 => "min:1"
          ]
          "material.0" => array:1 [
            0 => "required"
          ]
          "content" => array:2 [
            0 => "required"
            1 => "min:10"
          ]
        ]

.blade.php


<form id="project-create-form" action="{{route('projets.store')}}" method="POST" enctype="multipart/form-data">
            @csrf
            <div class="categories-box">
                <div class="presentation">
                    Choisir une catégorie
                </div>
                <div>
                    @if($errors->has('category'))
                    <div class="error-box">
                        <small><i class="fa fa-times" aria-hidden="true"></i> {{$errors->first('category')}}</small>
                    </div>
                    @endif
                    <div class="categories">         
                        @foreach ($categories as $enName => $frName)
                        <div>
                            <label for="{{$enName}}">
                                <input type="radio" id="{{$enName}}" name="category" class="category">
                                
                                <span>{{$frName}}</span>
                            </label>
                        </div>
                        @endforeach
                    </div>
                </div>
            </div>


            <div class="uk-margin">
                @if($errors->has('title'))
                <div class="error-box">
                    <small><i class="fa fa-times" aria-hidden="true"></i> {{$errors->first('title')}}</small>
                </div>
                @endif
                <div class="input-and-characters-num">
                    <input class="uk-input post-title" name="title" type="text" maxlength="{{$maxChars}}"
                        placeholder="Titre du projet">
                    <div class="characters-num" id="charNum">{{$maxChars}}</div>
                </div>
            </div>

            <div class="uk-margin">
                @if($errors->has('thumbnail'))
                <div class="error-box">
                    <small><i class="fa fa-times" aria-hidden="true"></i> {{$errors->first('thumbnail')}}</small>
                </div>
                @endif <div class="thumbnail-box">

                    <label for="thumbnail" class="thumbnail-label">
                        <i class="fa fa-cloud-upload" aria-hidden="true"></i>
                        ajouter une image thumnail pour votre projet !
                        <input type="file" id="thumbnail" name="thumbnail" class="thumbnail">
                        <div id="image_preview">
                        </div>
                    </label>
                </div>
            </div>

            <div class="uk-margin inputs-box">
                <div class="presentation">
                    <h4>Liste des besoins</h4>
                    <small>Ajoutez ce dont vous avez besoin pour ce projet</small>
                </div>
                <div class="boxes">

                    @if($errors->has('material.*'))
                    <div class="error-box">
                        <small><i class="fa fa-times" aria-hidden="true"></i> {{$errors->first('material.*')}}</small>
                    </div>

                    @endif

                    @for($i = 1; $i <=3 ; $i++) @php if($i==1){ 
                        
                        $button='material-add-button' ; $icon='fa-plus' ;
                        $placeholder='ex: 5 boîtes en carton' ; 

                    } else { 
                        
                        $button='material-remove-button' ;
                        $icon='fa-times' ; $placeholder='' ; 
                        
                    }
                    
                    @endphp 
                    
                    <div class="input-box" id="input-box-{{$i}}">
                        <input class="uk-input material-input" name="material[]" id="{{$i}}" type="text"
                            placeholder="{{$placeholder}}">

                        <button class="uk-button {{$button}}" type="button" id="btn-{{$i}}"><i class="fa {{$icon}}"
                                aria-hidden="true"></i>
                        </button>
                    </div>

                    @endfor
                </div>

        </div>

//my test 


/*
* @test
*/

    public function the_fields_are_filled()
    {
         
            $user = factory(User::class)->create();
            $project = factory(Project::class)->create();
            $cat = factory(Category::class)->create();
            $material = factory(Material::class, 2)->create();

            $mat1 = Material::find(1);
            $mat2 = Material::find(2);


            // dd($mat1, $mat2);

            //relation between user and projects 
            $user->projects()->save($project);


            // relation between project and user
            $project->user()->associate($user)->save();


            //relation between project and material
            // $project->materials()->save($material);


            //si plusieurs materiaux
            $project->materials()->saveMany([$mat1, $mat2]);


            //relation between material and project
            $mat1->project()->associate($project)->save();
            $mat2->project()->associate($project)->save();
     
            // dd($project->materials->all());

            //relation between project and category
            $project->category()->save($cat);

            //relation between category and project
            $cat->categorizable()->associate($project)->save();



       
// dd($matId = $project->materials->pluck('id'));



// dd($user->projects);





// dd($user->projects);

        $response =  $this->actingAs($user)->post(route('projets.store'),
              [
                    'category' => $project->category->id,
                    'user_id' => $project->user->id, 
                    'title' => $project->title, //pb -> titre déjà pris
                    'thumbnail' =>$project->thumbnail, // pas de thumbnail
                    'material[0]' => $project->materials->pluck('name'), // pas de materiels
                    'content' => $project->content
                
                    ]
               
                ); 


// dump($response);

        $response->assertStatus(302)->assertSessionHasNoErrors();
    }  

I don't know why. Can you help me please?