Java サーバーがクライアントのリクエストに応答できないのはなぜですか?

public class Server {

    public static void main(String[] args) throws IOException {
        ServerSocket ss = null;
        Socket s = null;
        try {
            // Create a server socket and listen on port 34000
            ss = new ServerSocket(34000);

            // Accept an incoming connection from a client
            s = ss.accept();

            // Create input and output streams for communication
            BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream()));
            OutputStreamWriter out = new OutputStreamWriter(s.getOutputStream());

            // Continuously read messages from the client
            while (true) {
                String string = in.readLine();
                if (string != null) {
                    System.out.println("br: " + string);

                    // Respond to the "end" message from the client
                    if (string.equals("end")) {
                        out.write("to end");
                        out.flush();
                        out.close();
                        System.out.println("end");
                        // break;
                    }
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // Close the socket connections
            s.close();
            ss.close();
        }
    }
}

public class Client {

    public static void main(String[] args) {
        Socket socket = null;
        try {
            // Create a client socket and connect to the server on port 34000
            socket = new Socket("localhost", 34000);
            
            // Create input and output streams for communication
            BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            OutputStreamWriter out = new OutputStreamWriter(socket.getOutputStream());

            // Send a message to the server
            String string = "end";
            out.write(string);
            out.flush();

            // Listen for the server's response
            while (true) {
                String string2 = in.readLine();
                if (string2.equals("to end")) {
                    System.out.println("yes sir");
                    break;
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            // Close the socket connection
            socket.close();
        }
    }
}

string = "end\r\n";
out.write(string);
out.flush();

out.write("to end\r\n");
out.flush();