Получен неожиданный EOF или 0 байтов из транспортного потока.Настройки ServicePointManager не исправляются

Question

Я получаю это исключение, когда пытаюсь загрузить строку с помощью WebClient.Я пытался во многих случаях настроить ServicePointManager:

ServicePointManager.Expect100Continue: true and false

ServicePointManager.SecurityProtocol: SecurityProtocolType.Ssl3 

и

SecurityProtocolType.Tls12 

и

(SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls12) 

и все Tls и все протоколы.Каждая комбинация была использована.Не работает.
Но если я использую команду curl - я хорошо получаю json.

curl -X GET https://myurl/2019-05-29

То же поведение в браузере
Система: Windows Server 2012 R2
.NET: Framework 4.6.1

Callstack :
Failed to get fixtures from URI=https://myurl/2019-05-29. System.Net.WebException: An exception occurred during a WebClient request. --->System.IO.IOException: Received an unexpected EOF or 0 bytes from the transport stream. at System.Net.ConnectStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.WebClient.DownloadBitsState.RetrieveBytes(Int32& bytesRetrieved) at System.Net.WebClient.DownloadBits(WebRequest request, Stream writeStream, CompletionDelegate completionDelegate, AsyncOperation asyncOp) at System.Net.WebClient.DownloadDataInternal(Uri address, WebRequest& request) --- End of inner exception stack trace --- at System.Net.WebClient.DownloadDataInternal(Uri address, WebRequest& request) at System.Net.WebClient.DownloadString(Uri address) at System.Net.WebClient.DownloadString(String address)

Код с одним регистром:

ServicePointManager.ServerCertificateValidationCallback +=
              (sender, cert, chain, sslPolicyErrors) => true;
ServicePointManager.Expect100Continue = true;
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls |
                                       SecurityProtocolType.Tls11 | 
                                       SecurityProtocolType.Tls12 |
                                       SecurityProtocolType.Ssl3;

using (var wc = new WebClient())
{
    try
    {
       var json = wc.DownloadString(uri);
       return json;
    }
    catch (Exception e)
    {
        return null;
    }
}