Google Adwords saving Server Side conversion Tracking through Measurement Protocol

I am using:

https://developers.google.com/analytics/devguides/collection/protocol/v1/

for server side tracking.

This is the set-up:

• Google analytics account.
• Google adwords account.
• Adwords account is linked to the analytics account.

I create an ad in adwords, the user clicks the ads, the user visits the third party website, the third party website make a https POST request with the visitor gclid from adwords. This is stored in a mysql database.

In the google adwords account I have an event for conversion created. (Using the offline tracking conversion works, but the only reason why I would prefer to use measurement protocol is because the offline tracking only accepts the conversions after 90 minutes. )

And I send the page views and conversion in this way:

/**  * @param $gclid  * @param $clientId  * @return \TheIconic\Tracking\GoogleAnalytics\AnalyticsResponse  */ private function sendPageView($gclid, $clientId){     $this->analytics         ->setProtocolVersion(1)         ->setTrackingId(self::GLOBAL_TRACKING_ID)         ->setGoogleAdwordsId($gclid)         ->setAnonymizeIp(true)         ->setClientId($clientId);     return $this->analytics->sendPageview(); } /**  * @param $gclid  * @param $clientId  * @return \TheIconic\Tracking\GoogleAnalytics\AnalyticsResponse  */ private function sendConversion($gclid, $clientId, $url){     $this->analytics         ->setProtocolVersion(1)         ->setTrackingId(self::GLOBAL_TRACKING_ID)         ->setGoogleAdwordsId($gclid)         ->setAnonymizeIp(true)         ->setClientId($clientId)         ->setEventAction('s2s')         ->setEventCategory('Lead')         ;     return $this->analytics->sendEvent(); } 

Response:

object(TheIconic\Tracking\GoogleAnalytics\AnalyticsResponse)#1008 (3) {   ["httpStatusCode":protected]=>   int(200)   ["requestUrl":protected]=>   string(164) "https://ssl.google-analytics.com/collect?v=1&tid=UA-1XXXXX-1&gclid=EAIaIQobChMInvrxopLZ5gIVXXXXXXXXXXXXXXXXXXXX_BwE&aip=1&cid=1&ea=s2s&ec=Lead&t=event"   ["responseBody":protected]=>   string(35) "GIF89a�����,D;" } 

So the response is 200, however the conversion is not recorded anywhere, and I am not sure if I should be sending any other parameter, or how to debug the issue.