title: Docusign /oauth/token endpoint return page instead of json with bearer C#
body: <p>I went through the OAuth2 proccess in DocuSign API, I follow all the steps using official docs, but when I tried to perform the request in order to get the the AccessToken I received an HTML as response, indicating something like "DocuSign is temporarily unavailable. Please try again momentarily." Although the http response is 200(OK), The weird stuff is when I test with the same values on Postman I get the correct response.</p>
  
  <p>This is my code</p>
  
  <pre><code>public static DocuSignBearerToken GetBearerToken(string AccessCode, bool RefreshToken = false)
      {
          string AuthHeader = string.Format("{0}:{1}", DocuSignConfig.IntegratorKey, DocuSignConfig.SecretKey);
          var client = new RestClient("http://account-d.docusign.com");
          client.Authenticator = new HttpBasicAuthenticator(DocuSignConfig.IntegratorKey, DocuSignConfig.SecretKey);
          var request = new RestRequest("/oauth/token", Method.POST);
          request.AddHeader("content-type", "application/x-www-form-urlencoded");
          request.AddHeader("authorization", "Basic " + Base64Encode(AuthHeader));
          if(!RefreshToken)
              request.AddParameter("application/x-www-form-urlencoded", string.Format("grant_type=authorization_code&amp;code={0}", AccessCode), ParameterType.RequestBody);
          else
              request.AddParameter("application/x-www-form-urlencoded", string.Format("grant_type=refresh_token&amp;refresh_token={0}", AccessCode), ParameterType.RequestBody);
  
          IRestResponse response = client.Execute(request);
  
          var responseString = response.Content;
          DocuSignBearerToken Result = JsonConvert.DeserializeObject&lt;DocuSignBearerToken&gt;(responseString);
  
          return Result;
      }
  </code></pre>