PHPUnit and Laravel responds 401 status code it should return 422

I'm studying Laravel 11 and I have my first problem using PHPStorm (I don't know if it's my test or not).

I have this controller:

<?php

namespace App\Http\Controllers;

use App\Http\Controllers\Controller;
use Illuminate\Http\Request;

class LoginController extends Controller
{
  public function login(Request $request)
  {
    $request->validate([
      'email' => 'email|string',
      'password' => 'required|min:8',
    ]);

    $credentials = request(['email', 'password']);

    if (!$token = auth()->attempt($credentials)) {
      return jsonResponse(status: 401, message: 'Unauthorized');
    }

    return jsonResponse(data: [
      'token'      => $token,
      'expires_in' => auth()->factory()->getTTL() * 60
    ]);
  }
}

My test code:

public function test_email_must_be_required(): void
  {
    $credentials = ['password' => 'password'];

    $response = $this->postJson("{$this->apiBase}/login", $credentials);

    $response->assertStatus(422);
    $response->assertJsonStructure(['message', 'data', 'status', 'errors' => ['email']]);
    $response->assertJsonFragment(['errors' => ['email' => ['The email field is required.']]]);
  }

But when I run the test, I have the following response:

However, it should not return 401 because the email in the test credentials is not being sent. It should return response code 422 instead.

[EDIT] When I change my validate method:

...
   'email' => 'required|email|string',
...

My code response is 200:

[EDIT 2]

This is my routes/api.php code: