php get error Unknown SSL protocol error in connection

I should connect to a webservice that use Basic Authntication and GET method to fetch a json string. when I enter url in browser I get correct result but when I try it using cUrl I get error bellow:

Unknown SSL protocol error in connection to www.example.com:443 

here is code:

$url = "https://www.example.com/api/Voucher/VerifyDiscountCode?discountCode=test&cellPhoneNumber=123456&otp=false";
$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_TIMEOUT, 120);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
curl_setopt($curl, CURLOPT_HEADER, 0);
//curl_setopt($curl, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
curl_setopt($curl, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($curl, CURLOPT_USERPWD, "test:test");
$data = curl_exec($curl);
if($data === false) $data = curl_error($curl);
$status_code = curl_getinfo($curl, CURLINFO_HTTP_CODE);
curl_close($curl);

echo $data;

note: it is funny that this code works in my local pc but not in server! I am sure it is not firewall thing. not sure it is from php configuration or what?