Sending SysLog message through TCP with SyslogNet.Client

I'm trying to send a message to my syslog server in Windows 10, created with SysLog Watcher.

The message is sent through TCP and UDP protocols but using TCP the Severity and Facility flags are not sent.

With UDP everything works fine!

I've already tried Kiwi Server and the problem is the same.

I am using the nuget SyslogNet.Client and I send the UDP message this way:

SysLogMessage msg = new SysLogMessage(SyslogMessage(
                DateTimeOffset.Now,
                14, // Facility - LogAlert
                2, // Severity - Critical
                LocalHostName ?? Environment.MachineName, // MachineName
                "AppName", // AppName
                null, // ProcId
                "MessageType", // Message type name
                "message to be sent"); // message to be sent


ISyslogMessageSerializer serializer = options.SyslogVersion == "5424"
                        ? (ISyslogMessageSerializer)new SyslogRfc5424MessageSerializer()
                        : options.SyslogVersion == "3164"
                            ? (ISyslogMessageSerializer)new SyslogRfc3164MessageSerializer()
                            : (ISyslogMessageSerializer)new SyslogLocalMessageSerializer();

                    SyslogMessage msg = CreateSyslogMessage(options);

                    ISyslogMessageSender sender = null;
                    if (options.NetworkProtocol.Equals("tcp", StringComparison.InvariantCultureIgnoreCase))
                    {
                        sender = IsEncryptedTCP ?
                                   (ISyslogMessageSender)new SyslogEncryptedTcpSender(options.SyslogServerHostname, options.SyslogServerPort)
                                   : (ISyslogMessageSender)new SyslogTcpSender(options.SyslogServerHostname, options.SyslogServerPort);
                    }
                    else if (options.NetworkProtocol.Equals("udp", StringComparison.CurrentCultureIgnoreCase))
                    {
                        sender = (ISyslogMessageSender)new SyslogUdpSender(options.SyslogServerHostname, options.SyslogServerPort);
                    }
                    else
                    {
                        sender = (ISyslogMessageSender)new SyslogLocalSender();
                    }
                    #endregion

                    sender.Send(msg, serializer);

Again, this works just fine with UDP but when using TCP or LocalSend, the message does not send the flags Facility and Severity!

I would expect to see the flags Facility and Severity being sent through the SyslogNet.Client over TCP protocol!

Thanks!