problem with curl in php on ring-out

$ch = curl_init();

curl_setopt($ch, CURLOPT_URL,"https://platform.devtest.ringcentral.com/restapi/v1.0/account/~/extension/~/ring-out");

curl_setopt($ch, CURLOPT_POST, 1);

curl_setopt($ch, CURLOPT_POSTFIELDS,

http_build_query(array('from' => '+12048184079',

'to' => '+17604762222'

)));

curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

$headers = [

"Content-Type: application/json",

"Accept: application/json",

"Authorization: Bearer U0pDMTFQMDFQQVMwMHxBQUFtdWhQcG5lYk4xbUIwc2pyaXpqTVZJZnlxUWhENlEtc2NRcTNxYmZaRXl5Qk9nSWk2RDFiMjVFTy0zaXhsVGlWNF9QWWRPMEVYNENYQjd4dmJsWHJoVTBsTVl2VlA1XzNIczcycTVONm13eDY5d3o3YWkwN3l5Wkt3clFLVDl0Y3FmajJQZ0tRSUtmRnhjNGJua1lHbmxxSElJTzBnOUxab0dZR19MVlo5bGhDU2pMcE1oYm5jRG9icVRYbUswSm14VzI3VmdrNjR2aVZxUGt6bU9aOUN8amhaMGtnfFZFM1ZGamhpaTdKcjc2dkRzSDEzMGd8QUE"

];

curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

$server_output = curl_exec($ch);

echo "<pre>"; print_r($server_output); die;

curl_close ($ch);

output: -

{    "errorCode" : "InvalidJson",    "message" : "Unrecognized token 'from': was expecting 'null', 'true', 'false' or NaN
 at line: 1, column: 6",    "errors" : [ ] 

}