OnDisconnecting after received message from client

[tardeli2]

Hi, Im using the TcpServer to start a service and when the client connects message is received but immediately OnDisconnect() is triggered. After I monitor the messages via Wireshark I see following:

As you can see the client was able to sent message but after that it sends [FIN, ACK] which means the client informs the server that no more data is expected to be sent. This seems like a valid TCP flow. The problem is that the server is responding to that with another [FIN, ACK] and after that one the client closes the connection which results in triggering the OnDisconnecting().
Is there a way to avoid sending the [FIN, ACK] from the server, because that one is signaling the client to close the session?