question

below is the C# code.  suggest any changes if required. This returns authorization failure code = 1.  do I need to change any settings or configuration on ringcentral setup? if you can point to any mistakes following code is making.
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var formData = new System.Collections.Specialized.NameValueCollection(); formData["Username"] = "Username";
formData["Password"] = "Alphanumeric Password";
formData["Recipient"] = "8664376797";
formData["Coverpagetext"] = "Test Fax Content";
 formData["Resolution"] = "High";
 string serverUrl = " https://service.ringcentral.com/faxapi.asp";
 Uri RequestUri = new Uri(serverUrl);
 using (var multiPartContent = new MultipartFormDataContent())
 {
     foreach (string key in formData)
     {
           multiPartContent.Add(new StringContent(formData[key]), "\"" + key + "\"");
     }
HttpRequestMessage httpRequest = new HttpRequestMessage();
httpRequest.Method = HttpMethod.Post;
httpRequest.RequestUri = RequestUri;
httpRequest.Content = multiPartContent;
try
{
     HttpClient httpClient = new HttpClient();
     var httpResponse1 =    httpClient.SendAsync(httpRequest);
     var result = httpResponse1.Result;
     Response.Write(result.Content);
 }
 finally
 {
     if (httpRequest != null)
     { httpRequest.Dispose();
     }
 }