protected function handleFailedNotifications($notifiable, Notification $notification, $response)
    {
        $results = $response->getResults();

        foreach ($results as $token => $result) {
            if (! isset($result['error'])) {
                continue;
            }

            $this->events->dispatch(
                new NotificationFailed($notifiable, $notification, get_class($this), [
                    'token' => $token,
                    'error' => $result['error'],
                ])
            );
        }
    }