VB.NET POST 响应 InternalServerError

如何解决VB.NET POST 响应 InternalServerError

我需要进行 POST 并获取返回的令牌。但是请求/响应只是返回错误 500。

我的功能：

Public Function SendRequest() As String

    Dim token As String = ""


      Dim data = Encoding.UTF8.GetBytes("{
  ""Login"": ""login"",""Senha"": ""pass"",""GrantType"": ""password""
}")

    System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls Or SecurityProtocolType.Tls11 Or SecurityProtocolType.Tls12

    Dim httpRequest As HttpWebRequest
    Dim httpResponse As HttpWebResponse

    Try

        httpRequest = WebRequest.Create("https://www.pagtel.com.br/Hub360/Contel/api/Login")
        httpRequest.Method = "POST"
        httpRequest.ContentType = "application/json"
        httpRequest.ContentLength = data.Length

        Dim requestStream = httpRequest.GetRequestStream
        requestStream.Write(data,data.Length)

        httpResponse = httpRequest.GetResponse()

    Catch wex As WebException

        If wex.Status = WebExceptionStatus.ProtocolError Then

            httpResponse = wex.Response

            Dim erro As String = httpResponse.StatusCode.ToString()

            httpResponse.Close()

        End If

    End Try

    Return token

End Function

响应包含一个名为：accesstoken 的字段。

我更改了登录名和密码。

最奇怪的是，在 Postman 中，它运行得很好。没有错误和状态 200。 但是当在我的应用程序中时，只返回错误 500。