duplicate model entries in laravel mailable

I'm trying to put send an email using mailables and jobs.

However for some reason the attachments and the body is duplicated

Job:

class SendReservationConfirmed implements ShouldQueue
{
    protected $subscriber;
    use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;
    public function __construct(Subscriber $subscriber)
    {
        $this->subscriber = $subscriber;
    }
    public function handle()
    {
        $email = new ReservationConfirmed($this->subscriber);
        Mail::to($this->subscriber->email)->send($email);
    }
}

Mailable:

class ReservationConfirmed extends Mailable
{
    use Queueable, SerializesModels;
    public $subscriber;
    public function __construct(Subscriber $subscriber)
    {
        $this->subscriber = $subscriber;
    }
    public function build()
    {
        $attachments = [];
        $email = $this->view('emails.confirm-new')
                ->with(['subscriber' => $this->subscriber]);

The job only get's executed once, the model i'm dispatching has the following data:

"data": {
    "id": 119,
    "first_name": "",
    "reservations": [
        {
            "spot_id": 686,
            "spot": {
                "id": 686,
                "zone": {
                    "id": 125,
                    "number": 123,
                    "name": "",
                }
            }
        },

via Chebli Mohamed