Paypal certificate problem

hi sorry for english i use the paypal code on github :

https://github.com/paypal/ipn-code-sampl...palIPN.php

I insert the cacert.pem inside a folder in writable , this is my code :

PHP Code:

        if ($this->use_local_certs) {
            curl_setopt($ch, CURLOPT_CAINFO, WRITEPATH.'/uploads/Paypal/cacert.pem');
        } 


But in my ipn log i have :  cURL error: [60] SSL certificate problem: unable to get local issuer certificate
This is my server screenshot :
https://imgur.com/ljuXH6e.png
Why ?