public function ticket($forceRefresh = false)
    {
        $key = self::GROUP_TICKET_CACHE_PREFIX.$this->getAccessToken()->getFingerprint();
        $ticket = $this->getCache()->fetch($key);

        if (!$forceRefresh && !empty($ticket)) {
            return $ticket;
        }

        $result = $this->parseJSON('get', [self::API_GROUP_TICKET, ['type' => 'contact']]);

        $this->getCache()->save($key, $result, $result['expires_in'] - 500);

        return $result;
    }