protected function getClient(array $auth)
    {
        $this->cookieFile = storage_path() . '/guzzlehttp/cookies/vonage/' . $auth['username'] . '.txt';

        $cookieJar = new FileCookieJar($this->cookieFile, true);

        $this->client = new Client(array('base_uri' => $this->base_uri, 'cookies' => $cookieJar));

        $response = $this->client->get($this->base_uri . '/appserver/rest/user/null', [
            'cookies' => $cookieJar,
            'query' => [
                'htmlLogin' => $auth['username'],
                'htmlPassword' => $auth['password']
            ],
            'headers' => ['X-Vonage' => 'vonage']
        ]);

        return $this->client;
    }