Having trouble ending a game

I had to make a minefield game for my java class, in which a user must click 10 squares without hitting the mine. I was able to make it so when the mine is clicked, all the other squares change their color and the game ends. However, i need to add a congratulatory message in the NORTH JFrame region when the user clicks 10 squares successfully. How would i go about doing this? I added an if statement for this,
however it doesnt seem to be working, so i'm assuming i did it wrong.

Code java:

  import javax.swing.*;
  import java.awt.*;
  import java.awt.event.*;
 
  public class Minefield extends JFrame implements ActionListener
  {
 
  	JPanel[] aPanel = new JPanel[20];
  	JButton[] aButton = new JButton[20];
  	int bomb = (int) (Math.random() * 100) % 20;
  	int counter;
  	JLabel bLab = new JLabel("");
 
  	public Minefield()
  	{
  		setTitle("Mine Field");
  		setSize(500, 500);
  		setVisible(true);
  		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  		setLayout(new GridLayout(5, 5));
 
  		for (int i = 0; i<aPanel.length; i++)
  		{
  			aPanel[i] = new JPanel(new GridLayout(1, 1));
  			aButton[i] = new JButton("");
  			aButton[i].setBackground(Color.BLUE);
  			add(aPanel[i]);
  			aPanel[i].add(aButton[i]);
  			aButton[i].addActionListener(this);
 
  		}//end forloop
 
  	}
 
  	public void actionPerformed(ActionEvent e)
  	{
  		Object source = e.getSource();
  		counter++;
  		for (int i = 0; i<aButton.length; i++)
  		{
  			if(aButton[i] == source)
  			{
  				if(i == bomb)
  				{
  					aButton[i].setBackground(Color.RED);
 
  					for (int a = 0; i<aButton.length; a++)
  					{
  						if(a != bomb)
  						{
  							aButton[a].setBackground(Color.WHITE);
  						}
  					}
  				}
  				else
  				{
  					aButton[i].setBackground(Color.WHITE);
 
  					if(counter == 10)
  					{
  						bLab.setText("You win!");
  					}
  				}
  			}
  		}//end forloop
  	}
 
  	public static void main(String[] args)
  	{
  		Minefield b1 = new Minefield();
  	}
  }