first HttpWebResponse.GetResponseStream() fails, second one works? - httpwebresponse

Question

I am creating a program that auto login into a website using forms authentication. When ever I call my method to connect to the website, it returns me a empty document text. However, if I call the same method a second time, it works perfectly.
Here is my code :
//perform authentication and stores the session in the cookiecontainer
private void loginToSite()
{
// prepare the web page we will be asking for
request = (HttpWebRequest)
WebRequest.Create(#"http://diary.com/notes/my_journal");
request.KeepAlive = true;
//========================================
//start of forms authentication parameters
//========================================
string authInfo = username + ":" + password;
authInfo = Convert.ToBase64String(Encoding.Default.GetBytes(authInfo));
request.Headers["Authorization"] = "Basic " + authInfo;
//========================================
//end of forms authentication parameters
//========================================
request.ContentType = "text/html";
request.Method = "GET";
request.AllowAutoRedirect = true;
request.Referer = #"http://diary.com/";
request.CookieContainer = new CookieContainer();
// execute the request
HttpWebResponse response = (HttpWebResponse)
request.GetResponse();
// we will read data via the response stream
Stream resStream = response.GetResponseStream();
container = request.CookieContainer;
//assign the http content to myWB for manipulation
//myWB is a WebBrowser object that have been declared
myWB.DocumentStream = resStream;
//prevent script errors from popping up
myWB.ScriptErrorsSuppressed = true;
MessageBox.Show(myWB.DocumentText);
}