VB.NET中带承载授权的WebRequest

我需要向远程服务器发送POST请求，这需要承载授权。 这是我的VB.NET代码：

Public Shared Function syncAsana() As String
    Dim result As String
    Try
        Dim token As String = "TOKEN"
        Dim uri As String = "https://URL/api/1.0/tasks"
        Dim postData As String = "assignee=email&notes=TEST_NOTES&name=NOME 1&projects=123985"
        Dim byteArray As Byte() = Encoding.UTF8.GetBytes(postData)
        Dim request As WebRequest = WebRequest.Create(uri)
        request.Method = "POST"
        request.PreAuthenticate = True
        request.Headers.Add("Authorization", "Bearer " & token)
        request.ContentType = "application/x-www-form-urlencoded"
        request.ContentLength = byteArray.Length
        Dim dataStream As Stream = request.GetRequestStream()
        dataStream.Write(byteArray, 0, byteArray.Length)
        dataStream.Close()
        Dim response As WebResponse = request.GetResponse()
        Using dataStream1 As Stream = response.GetResponseStream()
            ................
            result = responseFromServer
        End Using
        response.Close()
    Catch ex As Exception
        result = ex.Message
    End Try
    Return result
End Function

问题是我总是在底层连接关闭时收到错误消息：接收时发生意外错误 使用jquery/ajax或curl发出的请求同样有效。 我已经从VisualStudio启动的本地服务器和将代码放在生产服务器上进行了尝试。 你能告诉我哪里错了吗