title: Restsharp PUT custom header
body: <p>I have to use RestSharp to PUT some data into an API.</p>
  
  <p>The API resource is: /clients/services/finances/{finances-id}/subcategory/{subcategory-id}</p>
  
  <p>Apart from template parameters, there are some query parameters:
  organization-id (string)
  operator-id (string)</p>
  
  <p>And also, the request Content-Type must be application/xml</p>
  
  <p>The way I'm trying to create this PUT request using RestSharp:</p>
  
  <pre><code> RestClient client = new RestClient(url);
   client.Authenticator = Auth1Authenticator.ForRequestToken(Config.getVal("api_key"), Config.getVal("secret_key"));
   IRestRequest request = new RestRequest("", Method.PUT);
   request.RequestFormat = DataFormat.Xml;
   request.AddParameter("organization-id", Config.getVal("params.org")); 
   request.AddParameter("operator-id", "Accounting");
   IRestResponse response = client.Execute(request);
  </code></pre>
  
  <p>But I'm only get HTTP Status 415 - Unsupported Media Type</p>
  
  <p>Can you please help me to resolve this. GET request is working like a charm.</p>