HTTP POST Error Problem with Parameter json_data

Other Hardware Home Automation
6

I am using this =

char PostData[] = "{"operation":"core/create","class":"UserRequest","output_fields":"id","comment":"loquesea","fields":{"org_id":"1","title": "prueba_hospital","description":"prueba"}}";

if (client) {
client.println("POST /itop/web/webservices/rest.php?version=1.1 HTTP/1.1");
client.println("Host: 172.30.31.6");
client.println("Authorization: Basic YWRtaW46YWRtaW4="); // USUARIO Y CONTRASEÑA EN BASE 64
client.println("User-Agent: Arduino/1.8.5");
client.println("Content-Type: application/json");
client.print("Content-Lenght: ");
client.println(strlen(PostData));
client.println("Connection: close");
client.println();
client.print(PostData);
Serial.println("Post Realizado");
}else {
Serial.println("No se ha podido hacer el POST");
}

Sending =

POST /itop/web/webservices/rest.php?version=1.1 HTTP/1.1
Host: 172.30.31.6
Authorization: Basic YWRtaW46YWRtaW4=
User-Agent: Arduino/1.8.5
Content-Type: application/json
Content-Lenght: 165
Connection: close

{"operation":"core/create","class":"UserRequest","output_fields":"id","comment":"loquesea","fields":{"org_id":"1","title": "prueba_hospital","description":"prueba"}}

Response =

HTTP/1.1 200 OK
Date: Thu, 03 May 2018 15:32:31 GMT
Server: Apache/2.4.25 (Debian)
Set-Cookie: itop-cccc625803db2ea97734aa176e552d97=7qgb59ot28bol9tmp4u29h5825; path=/
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-cache
Pragma: no-cache
Access-Control-Allow-Origin: *
Content-Disposition: inline; filename=""
Content-Length: 58
Connection: close
Content-Type: application/json

{"code":3,"message":"Error: Missing parameter 'json_data"}