public function store($payload)
    {
        $payload['question'] = htmlentities($payload['question']);
        $payload['is_published'] = (isset($payload['is_published'])) ? (bool) $payload['is_published'] : 0;
        $payload['published_at'] = (isset($payload['published_at']) && !empty($payload['published_at'])) ? Carbon::parse($payload['published_at'])->format('Y-m-d H:i:s') : Carbon::now(config('app.timezone'))->format('Y-m-d H:i:s');

        return $this->model->create($payload);
    }