Tambola Game using java

//Below is a program for Tambola game which chooses a random number between 1 to 90 only once. I tried using many other techniques but by far this suited the best to me (Suggestions are entertained).

import java.util.Random;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

class Tambola extends JFrame implements ActionListener{
private JPanel pnlBoard, pnlButton;
private JButton btnNext, btnReset;
private JLabel lbl[] = new JLabel[90];
private JLabel lblNumber;
private int[] random_number = new int[90];
private int pos = 0;

public Tambola(String title){
super(title);
setVisible(true);
setSize(500,500);
setLayout(new BorderLayout());
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
addElements();
pack();
}

public void addElements(){

lblNumber = new JLabel("Tambola Game");
lblNumber.setHorizontalAlignment(0);
lblNumber.setFont(new Font("Cambria",Font.BOLD,28));
lblNumber.setForeground(Color.BLUE);
add(lblNumber,BorderLayout.NORTH);

pnlBoard = new JPanel();
pnlBoard.setLayout(new GridLayout(10,10));
add(pnlBoard,BorderLayout.CENTER);

for(int i = 0 ; i < random_number.length ; i++){
lbl[i] = new JLabel(""+(i+1));
lbl[i].setHorizontalAlignment(0);
pnlBoard.add(lbl[i]);
lbl[i].setOpaque(true);
lbl[i].setBackground(Color.WHITE);
random_number[i] = i;
}

Random rnd = new Random();
   for (int i = random_number.length - 1 ; i > 0 ; i--){
       int index = rnd.nextInt(i + 1);
       int a = random_number[index];
       random_number[index] = random_number[i];
       random_number[i] = a;
   }
   
   pnlButton = new JPanel();
   add(pnlButton,BorderLayout.SOUTH);
   pnlButton.setLayout(new GridLayout(2,2));
 
btnNext = new JButton("Next");
pnlButton.add(btnNext);
btnNext.addActionListener(this);

btnReset = new JButton("Reset");
btnReset.addActionListener(this);
pnlButton.add(btnReset);

lblNumber = new JLabel("Chossed Number: " +random_number[pos]);
pnlButton.add(lblNumber);
}

public void actionPerformed(ActionEvent e){
String command = e.getActionCommand();

if(command == "Next"){
lbl[random_number[pos]].setBackground(Color.BLACK);
lbl[random_number[pos]].setForeground(Color.WHITE);
lblNumber.setText("Chossed Number: " +(random_number[pos]+1));
pos++;
System.out.println (random_number[pos]);
}

else{
pos = 0;
for(int i = 0; i < lbl.length ; i++){
lbl[i].setBackground(Color.WHITE);
lbl[i].setForeground(Color.BLACK);
}
}
}

public static void main (String[] args) {
new Tambola("Tambola");
}
}