SockectComm.cpp
int retries = 6;
    while (retries > 0) {
        // Connect to server
        if (connect(sockfd, reinterpret_cast<sockaddr *>(&serv_addr), sizeof(serv_addr)) == SOCKET_ERROR) {
            std::cerr << "Unable to connect to server: " << WSAGetLastError() << std::endl;
            if (retries > 1) {
                int result = MessageBox(NULL, "Няма връзка със сървъра, n Следващ опит след 10 секунди", "Error",
                                        MB_RETRYCANCEL | MB_ICONERROR);
                if (result == IDCANCEL) {
                    return false; // User clicked Cancel, return false
                }
                Sleep(10000); // Sleep for 10 seconds before retrying
            }
            retries--;
        } else {
            return true; // Connection successful
        }
    }

    // If all retries failed, clean up and return false
    closesocket(sockfd);
    WSACleanup();
    return false;
}


//--------------------------------------------------------------------------------------------

    Finalizetpayment.cpp

  void FinalizePayment::generateCardPayment(const int &receiptId, int terminalId, float paymentSum) {
        m_query->Close();
        m_query->SQL->Text = "SELECT pos_name FROM ref_pos_account WHERE REF_POS_ACCOUNT_ID = :REF_POS_ACCOUNT_ID";
        m_query->ParamByName("REF_POS_ACCOUNT_ID")->AsInteger = terminalId;
        m_query->ExecQuery();

        bool datecsFound = false;
        while (!m_query->Eof) {
            AnsiString posNameAnsi = m_query->FieldByName("pos_name")->AsString;
            std::string posName = posNameAnsi.c_str();

            if (posName.find("Датекс") != std::string::npos) {
                datecsFound = true;
                break;
            }

            m_query->Next();
        }

        m_query->Close();

        // Proceed with the socket communication only if "Датекс" terminal is found
        int transactionNo = 0;
        if (datecsFound) {
            // Socket communication
            float totalPrice = getTotal(receiptId);
            SocketCommunication socketComm;

            if (!socketComm.connectToServer()) {
                // It is returning answer from DatecsSocket in 10 seconds retrying to connect the server 6 times
                return;
            }

            std::ostringstream ss;
            ss << "{"sell": """", "sum": " << totalPrice << "}";
            std::string jsonData = ss.str();

            if (!socketComm.sendJSONData(jsonData)) {
                return;
            }

            int transactionStatus;
            if (!socketComm.waitForUpdates(transactionStatus, transactionNo)) {
                return;
            }

            if (transactionStatus != PAY_TRANSACTION_APPROVED) {
                throw std::runtime_error("Моля изберете друг метод на плащане или пробвайте отново с карта!");
            }
        }

        // Perform the database query regardless of the terminal type
        try {
            m_query->Close();
            m_query->SQL->Text = "SELECT RECEIPT_SUM, PAYMENT_ID FROM POS_MAKE_PAYMENT_FROM_RECEIPT2(:GS_RECEIPTS_HEAD_ID,"
                                 " :REF_POS_ACCOUNT_ID, :PAYMENT_SUM, :DATECS_TRANSACTION_ID)";
            m_query->ParamByName("GS_RECEIPTS_HEAD_ID")->AsInteger = receiptId;
            m_query->ParamByName("REF_POS_ACCOUNT_ID")->AsInteger = terminalId;
            m_query->ParamByName("DATECS_TRANSACTION_ID")->AsInteger = transactionNo;
            if (paymentSum != 0)
                m_query->ParamByName("PAYMENT_SUM")->AsFloat = paymentSum;
            else
                m_query->ParamByName("PAYMENT_SUM")->Clear();

            m_query->ExecQuery();
            m_query->Close();
        } catch (const std::exception &e) {
            // Handle the exception, perhaps log it
        }
    }

I am trying to use “Cancel button” from SocketComm.cpp in Finalizepayment.cpp , when is pressed “Cancel” to stop tries to connect and to proceed with other function to execute the database query , even is not connected. just to save the payment in database.

For now is only terminating everything , and does not save anything in the database.