发送电子邮件时我无法访问对象的内容

Question

I want to send an email in my Laravel 5.8 instance. I create a mail file and a blade and then pass the message as an object to my mail. When I send an email with all objects, the email is sent successfully. However, when I try to access the attribute from the object, the email is not sent.

Controller

public function store(Request $request)
{
   $request->validate([
        'email' => 'required|email',
        'name' => 'required',
        'message' => 'required',
        'phone_number' => 'required'
    ]);

    $message = new ContactUs;
    $message->name = $request->name;
    $message->email = $request->email;
    $message->message = $request->message;
    $message->phone_number = $request->phone_number;

    if ($message->save()) {
        \Mail::to('[e-mail]')->send(new TestMail($message));
        Session::flash('message_sent', '');

        return back();
    }
}

Mail

public $test ;
public function __construct(ContactUs $test)
{
    $this->test = $test;
}

public function build()
{   
    $test = $this->test;

    return $this->view('emails.test',compact("test"));
}

Blade

<h1>Welcome</h1><div>{{$test}}</div>