With IPN simulator I VERIFIED and with Paypal I INVALID

[Capou]

Hello everyone, I have my class that works perfectly with IPN simulator I VERIFIED well in return but with paypal I invalid.

I search the forum and most often it is because of $ use_sandbox = true; but I put $ use_sandbox = false;

class PaypalIPN
{
    private $use_sandbox = false; //test sandbox true
    
    private $use_local_certs = true;
    const VERIFY_URI = 'https://ipnpb.paypal.com/cgi-bin/webscr';
    const SANDBOX_VERIFY_URI = 'https://ipnpb.sandbox.paypal.com/cgi-bin/webscr';
    const VALID = 'VERIFIED';
    const INVALID = 'INVALID';
        public function useSandbox()
    {
        $this->use_sandbox = true;
    }
    
    public function usePHPCerts()
    {
        $this->use_local_certs = false;
    }
    
    public function getPaypalUri()
    {
        if ($this->use_sandbox) {
            return self::SANDBOX_VERIFY_URI;
        } else {
            return self::VERIFY_URI;
        }
    }
   
    public function verifyIPN()
    {
        if ( ! count($_POST)) {
            throw new Exception("Missing POST Data");
        }
		
        $raw_post_data = file_get_contents('php://input');
        $raw_post_array = explode('&', $raw_post_data);
        $myPost = array();
        foreach ($raw_post_array as $keyval) {
            $keyval = explode('=', $keyval);
            if (count($keyval) == 2) {
                if ($keyval[0] === 'payment_date') {
                    if (substr_count($keyval[1], '+') === 1) {
                        $keyval[1] = str_replace('+', '%2B', $keyval[1]);
                    }
                }
                $myPost[$keyval[0]] = rawurldecode ($keyval[1]);
            }
        }
        $req = 'cmd=_notify-validate';
        $get_magic_quotes_exists = false;
        if (function_exists('get_magic_quotes_gpc')) {
            $get_magic_quotes_exists = true;
        }
        foreach ($myPost as $key => $value) {
            if ($get_magic_quotes_exists == true && get_magic_quotes_gpc() == 1) {
                $value = rawurlencode (stripslashes($value));
            } else {
                $value = rawurlencode ($value);
            }
            $req .= "&$key=$value";
        }
        $ch = curl_init($this->getPaypalUri());
        curl_setopt($ch, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_1);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $req);
        curl_setopt($ch, CURLOPT_SSLVERSION, 6);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 1);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
        if ($this->use_local_certs) {
            curl_setopt($ch, CURLOPT_CAINFO, __DIR__ . "/cert/cacert.pem");
        }
        curl_setopt($ch, CURLOPT_FORBID_REUSE, 1);
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30);
        curl_setopt($ch, CURLOPT_HTTPHEADER, array('Connection: Close'));
        $res = curl_exec($ch);
        if ( ! ($res)) {
            $errno = curl_errno($ch);
            $errstr = curl_error($ch);
            curl_close($ch);
            throw new Exception("cURL error: [$errno] $errstr");
        }
        $info = curl_getinfo($ch);
        $http_code = $info['http_code'];
        if ($http_code != 200) {
            throw new Exception("PayPal responded with http code $http_code");
        }
        curl_close($ch);
	
	
        if ($res == self::VALID) {		
	   return true;			
        } else {
            return false;
        }
	
    }
}

Is there a change to go from ipn simulator to paypal 

And I call the class normally

$ipn = new PaypalIPN();
// Use the sandbox endpoint during testing.
$ipn->useSandbox();
$verified = $ipn->verifyIPN();

if($verified){   }

header("HTTP/1.1 200 OK");

thanks a lot for your help

Capou