The API states that you should pass the parameters by GET
.
So change your $data
array like
$val=http_build_query($data);
$url='http://api.voicecloud.com/api.cgi';
$url.=$val;//Appending the params to the URL
and change your CALLAPI()
like
function CallAPI($method, $url, $data = false) {
$curl = curl_init();
//curl_setopt($curl, CURLOPT_POST, 1);//Commmented
//curl_setopt($curl, CURLOPT_POSTFIELDS, $data);//Commented
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
$result = curl_exec($curl);
print_r($result);
curl_close($curl);
}