php $_REQUEST not working when passing data through android - php

Question

<?php
if(isset($_REQUEST['body']))
{
$body = $_REQUEST['body'];
$api_key = "tHx7zm7eb7z3yKHtNb";
$password = "x";
$yourdomain = "appicmobile";
$ticket_data = json_encode(array(
"body" => $body
));
$url = "https://$yourdomain.freshdesk.com/api/v2/tickets/32/reply";
$ch = curl_init($url);
$header[] = "Content-type: application/json";
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, $header);
curl_setopt($ch, CURLOPT_HEADER, true);
curl_setopt($ch, CURLOPT_USERPWD, "$api_key:$password");
curl_setopt($ch, CURLOPT_POSTFIELDS, $ticket_data);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$server_output = curl_exec($ch);
$info = curl_getinfo($ch);
$header_size = curl_getinfo($ch, CURLINFO_HEADER_SIZE);
$headers = substr($server_output, 0, $header_size);
$response = substr($server_output, $header_size);
if($info['http_code'] == 201)
{
// "Ticket created successfully, the response is given below \n";
//echo "Response Headers are \n";
//echo $headers."\n";
//echo "Response Body \n";
echo "$response";
}
else
{
if($info['http_code'] == 404)
{
echo "Error, Please check the end point \n";
}
else
{
echo "Error, HTTP Status Code : " . $info['http_code'] . "\n";
echo "Headers are ".$headers;
echo "Response are ".$response;
}
}
curl_close($ch);
}
else {
echo "error";
}
?>
While entering data through android using php shows empty.I am using volley to pass the data.
I'm trying to pass data from Android to my PHP application, but it seems to POST method is not working well, once all $_REQUEST variables are empty.
Tried all the method get,post but still not working