Authentication fails when using Jsch SSH client

Question

I'm trying to connect to EC2 server using Jsch SSH client with RSA KeyPair, But it is giving me auth fail error. I have checked my configuration, even I'm able to connect to EC2 using terminal with same KeyPair.

package org.example;

import com.jcraft.jsch.ChannelShell;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import java.io.*;
import java.util.Scanner;
import java.util.UUID;
import java.util.regex.Pattern;

public class Ssh {
    private Session session = null;
    private final HostInfo host;
    private BufferedReader reader;
    private BufferedReader error;

    private ChannelShell channel;
    private BufferedWriter writer;

    public Ssh(HostInfo host) {
        this.host = host;
    }

    public void setup() throws Exception {
        JSch jSch = new JSch();
        jSch.addIdentity("aws-ssh.pem");
        session = jSch.getSession(host.getUsername(), host.getHost(), host.getPort());
        session.setConfig("StrictHostKeyChecking", "no");
        session.connect();

        channel = (ChannelShell) session.openChannel("shell");
        channel.connect();

        InputStream in = channel.getInputStream();
        InputStream err = channel.getExtInputStream();
        OutputStream out = channel.getOutputStream();
        reader = new BufferedReader(new InputStreamReader(in));
        writer = new BufferedWriter(new OutputStreamWriter(out));
        error = new BufferedReader(new InputStreamReader(err));
        
    }
}

Error:

Exception in thread "main" com.jcraft.jsch.JSchException: Auth fail
    at com.jcraft.jsch.Session.connect(Session.java:519)
    at com.jcraft.jsch.Session.connect(Session.java:183)
    at org.example.Ssh.setup(Ssh.java:30)
    at org.example.Main.main(Main.java:12)

I have try password authentication mode that works, but I want to authenticate via SSH key pair(.pem).