Help with error: Attempt to send to not connected connection {1}

Unity Engine
1

Tell me please. I use LLAPI.

With a slight increase in the number of transmitted packets connection is interrupted.
Аbout 1 minute connection is working properly, then still torn.

I get an error Attempt to send to not connected connection {1}
at line NetworkTransport.Send(m_hostId, item.connectionId, reliableFragmentedChannel, buffer, buffer.Length,out error);
connection Settings

 NetworkTransport.Init();
        ConnectionConfig config = new ConnectionConfig();
        unreliableChannel = config.AddChannel(QosType.Unreliable);
        reliableChannel = config.AddChannel(QosType.Reliable);
        reliableFragmentedChannel = config.AddChannel(QosType.ReliableFragmented);
        unreliableFragmentedChannel = config.AddChannel(QosType.UnreliableFragmented);
        config.MaxCombinedReliableMessageCount = 2048;
        config.MaxCombinedReliableMessageSize = 2048;
        config.MaxSentMessageQueueSize = 2048;
        config.IsAcksLong = true;
        HostTopology topology = new HostTopology(config, 10);
         m_hostId = NetworkTransport.AddHostWithSimulator(topology, 200, 400, 2500);

2

This means usually connection was closed by timeout. Most probably it is happened due big amount of packet loss. As you are using AddHostWithSimulator(), do you use ConnectWithSimulator function? Is it local environment or you have this when you are working via internet? Shortly, for correct answer I need more information