"Network subsystem is down" exception when post request in Linux Mono Launcher

[huseyincangunduz]

Hi There, i'm trying to integrate Middleware into our software. I'm running Middleware at Ubuntu 21.10 with Mono. But when i send post request i get that response with 500 code

<Fault xmlns="http://schemas.microsoft.com/ws/2005/05/envelope/none">
    <Code>
        <Value xmlns:a="http://schemas.microsoft.com/ws/2005/05/addressing/none">a:InternalServiceFault</Value>
    </Code>
    <Reason>
        <Text xml:lang="tr-TR">One or more errors occurred. (Network subsystem is down)</Text>
    </Reason>
    <Detail>
        <ExceptionDetail xmlns="http://schemas.datacontract.org/2004/07/System.ServiceModel" xmlns:i="http://www.w3.org/2001/XMLSchema-instance">
            <HelpLink i:nil="true"/>
            <InnerException>
                <HelpLink i:nil="true"/>
                <InnerException>
                    <HelpLink i:nil="true"/>
                    <InnerException i:nil="true"/>
                    <Message>Network subsystem is down</Message>
                    <StackTrace>  at System.Net.Http.ConnectHelper.ConnectAsync (System.String host, System.Int32 port, System.Threading.CancellationToken cancellationToken) [0x00110] in &lt;f7c2fcc82fee45dab8a414614bcfd337&gt;:0 </StackTrace>
                    <Type>System.Net.Sockets.SocketException</Type>
                </InnerException>
                <Message>Network subsystem is down</Message>
                <StackTrace>  at System.Net.Http.ConnectHelper.ConnectAsync (System.String host, System.Int32 port, System.Threading.CancellationToken cancellationToken) [0x001ac] in &lt;f7c2fcc82fee45dab8a414614bcfd337&gt;:0 
  at System.Net.Http.HttpConnectionPool.CreateConnectionAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) [0x00134] in &lt;f7c2fcc82fee45dab8a414614bcfd337&gt;:0 
  at System.Net.Http.HttpConnectionPool.WaitForCreatedConnectionAsync (System.Threading.Tasks.ValueTask`1[TResult] creationTask) [0x000a2] in &lt;f7c2fcc82fee45dab8a414614bcfd337&gt;:0 
  at System.Net.Http.HttpConnectionPool.SendWithRetryAsync (System.Net.Http.HttpRequestMessage request, System.Boolean doRequestAuth, System.Threading.CancellationToken cancellationToken) [0x00089] in &lt;f7c2fcc82fee45dab8a414614bcfd337&gt;:0 
  at System.Net.Http.RedirectHandler.SendAsync (System.Net.Http.HttpRequestMessage request, System.Threading.CancellationToken cancellationToken) [0x000ba] in &lt;f7c2fcc82fee45dab8a414614bcfd337&gt;:0 
  at System.Net.Http.HttpClient.FinishSendAsyncBuffered (System.Threading.Tasks.Task`1[TResult] sendTask, System.Net.Http.HttpRequestMessage request, System.Threading.CancellationTokenSource cts, System.Boolean disposeCts) [0x0017e] in &lt;f7c2fcc82fee45dab8a414614bcfd337&gt;:0 
  at fiskaltrust.Middleware.Interface.Client.Http.HttpDESSCD.ExecuteHttpPostAsync[T] (System.String urlVersion, System.String urlMethod, System.Object parameter) [0x000bd] in &lt;936809eecbbd4d97879fcf878650dea9&gt;:0 
  at fiskaltrust.Middleware.Interface.Client.Http.HttpDESSCD.SetTseStateAsync (fiskaltrust.ifPOS.v1.de.TseState state) [0x0007c] in &lt;936809eecbbd4d97879fcf878650dea9&gt;:0 
  at fiskaltrust.Middleware.Interface.Client.Common.RetryLogic.DESSCDRetryProxyClient+&lt;&gt;c_DisplayClass10_0.&lt;SetTseStateAsync&gt;b_0 (fiskaltrust.ifPOS.v1.de.IDESSCD proxy) [0x0006d] in &lt;77ee817b70d74858b85880aa6f2cac33&gt;:0 
  at fiskaltrust.Middleware.Interface.Client.Common.RetryLogic.RetryPolicyHandler`1+&lt;&gt;c_DisplayClass3_0`1[T,K].&lt;RetryFuncAsync&gt;b_0 () [0x000e7] in &lt;77ee817b70d74858b85880aa6f2cac33&gt;:0 
  at fiskaltrust.Middleware.Interface.Client.Common.RetryLogic.RetryPolicyHandler`1[T].RetryFuncAsync[K] (System.Func`2[T,TResult] action) [0x00146] in &lt;77ee817b70d74858b85880aa6f2cac33&gt;:0 
  at fiskaltrust.Middleware.Interface.Client.Common.RetryLogic.DESSCDRetryProxyClient.SetTseStateAsync (fiskaltrust.ifPOS.v1.de.TseState state) [0x00088] in &lt;77ee817b70d74858b85880aa6f2cac33&gt;:0 
  at fiskaltrust.Middleware.Localization.QueueDE.RequestCommands.RequestCommand.ProcessInitialOperationReceiptAsync (System.String transactionIdentifier, System.String processType, System.String payload, fiskaltrust.storage.V0.ftQueueItem queueItem, fiskaltrust.storage.V0.ftQueueDE queueDE, System.Boolean clientIdRegistrationOnly) [0x000a6] in &lt;857b4a7677264eb48486367cd34be343&gt;:0 
  at fiskaltrust.Middleware.Localization.QueueDE.RequestCommands.InitialOperationReceiptCommand.ExecuteAsync (fiskaltrust.storage.V0.ftQueue queue, fiskaltrust.storage.V0.ftQueueDE queueDE, fiskaltrust.ifPOS.v1.ReceiptRequest request, fiskaltrust.storage.V0.ftQueueItem queueItem) [0x0011e] in &lt;857b4a7677264eb48486367cd34be343&gt;:0 
  at fiskaltrust.Middleware.Localization.QueueDE.SignProcessorDE.PerformReceiptRequest (fiskaltrust.ifPOS.v1.ReceiptRequest request, fiskaltrust.storage.V0.ftQueueItem queueItem, fiskaltrust.storage.V0.ftQueue queue, fiskaltrust.storage.V0.ftQueueDE queueDE) [0x0011a] in &lt;857b4a7677264eb48486367cd34be343&gt;:0 
  at fiskaltrust.Middleware.Localization.QueueDE.SignProcessorDE.ProcessAsync (fiskaltrust.ifPOS.v1.ReceiptRequest request, fiskaltrust.storage.V0.ftQueue queue, fiskaltrust.storage.V0.ftQueueItem queueItem) [0x001c4] in &lt;857b4a7677264eb48486367cd34be343&gt;:0 
  at fiskaltrust.Middleware.Queue.SignProcessor.InternalSign (fiskaltrust.storage.V0.ftQueue queue, fiskaltrust.ifPOS.v1.ReceiptRequest data) [0x005ef] in &lt;a1aa2c0280f54485a8a05befb5976706&gt;:0 
  at fiskaltrust.Middleware.Queue.SignProcessor.InternalSign (fiskaltrust.storage.V0.ftQueue queue, fiskaltrust.ifPOS.v1.ReceiptRequest data) [0x00970] in &lt;a1aa2c0280f54485a8a05befb5976706&gt;:0 
  at fiskaltrust.Middleware.Queue.SignProcessor.ProcessAsync (fiskaltrust.ifPOS.v1.ReceiptRequest request) [0x0018e] in &lt;a1aa2c0280f54485a8a05befb5976706&gt;:0 
  at fiskaltrust.Middleware.QueueSynchronizer.LocalQueueSynchronizationDecorator.ProcessReceipts () [0x000bf] in &lt;bfe073a76c55438f84f05dd2b1d1975e&gt;:0 
  at fiskaltrust.Middleware.QueueSynchronizer.LocalQueueSynchronizationDecorator.ProcessAsync (fiskaltrust.ifPOS.v1.ReceiptRequest receiptRequest) [0x000c6] in &lt;bfe073a76c55438f84f05dd2b1d1975e&gt;:0 
  at fiskaltrust.Middleware.Queue.Queue.SignAsync (fiskaltrust.ifPOS.v1.ReceiptRequest request) [0x00077] in &lt;a1aa2c0280f54485a8a05befb5976706&gt;:0 </StackTrace>
                <Type>System.Net.Http.HttpRequestException</Type>
            </InnerException>
            <Message>One or more errors occurred. (Network subsystem is down)</Message>
            <StackTrace>  at System.Threading.Tasks.Task.ThrowIfExceptional (System.Boolean includeTaskCanceledExceptions) [0x00011] in &lt;162bccb5b7ae4c18b9c0cff8fdc3dfbc&gt;:0 
  at System.Threading.Tasks.Task`1[TResult].GetResultCore (System.Boolean waitCompletionNotification) [0x0002b] in &lt;162bccb5b7ae4c18b9c0cff8fdc3dfbc&gt;:0 
  at System.Threading.Tasks.Task`1[TResult].get_Result () [0x0000f] in &lt;162bccb5b7ae4c18b9c0cff8fdc3dfbc&gt;:0 
  at fiskaltrust.service.launcher.Helpers.Hosting.Wcf.Mono.MonoPos.Sign (fiskaltrust.ifPOS.v1.ReceiptRequest request) [0x0000c] in &lt;0cfdb9035548407eb1d7127ac3ea4b8c&gt;:0 
  at (wrapper managed-to-native) System.Reflection.RuntimeMethodInfo.InternalInvoke(System.Reflection.RuntimeMethodInfo,object,object[],System.Exception&amp;)
  at System.Reflection.RuntimeMethodInfo.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x0006a] in &lt;162bccb5b7ae4c18b9c0cff8fdc3dfbc&gt;:0 </StackTrace>
            <Type>System.AggregateException</Type>
        </ExceptionDetail>
    </Detail>
</Fault>

My request was that
POST http://localhost:1500/***/sign

{
    "ftCashBoxID": "*******",
    "ftPosSystemId": "1",
    "cbTerminalID": "001",
    "cbReceiptReference": "INIT",
    "cbReceiptMoment": "2022-05-29T00:46:21+03:00",
    "cbChargeItems": [],
    "cbPayItems": [],
    "ftReceiptCase": 4919338172267102211,
    "cbUser": "Admin"
}

Is there something i forget or i missed?

Thanks in advance