hello i have problem with my code. When i run the program it asking user to enter First Name Last name and account number but then when i will move to menu Check balance or different menu then when i comeback to main menu it ask me to enter information again and i dont have any idea how to fix it to ask me only
at the beginning to insert this information not everytime when i comeback to main manu

/**
 *
 * @author Karol Regulski
 */
import java.util.Scanner;
public class Main
{
	private double currentBal =1000;
	Scanner input = new Scanner(System.in);
 
	public String userfName()
	{
		System.out.print("Enter your First Name: ");
		String fname = input.next();
		return fname;
	}
 
	public String userlName()
	{
		System.out.print("Enter your Last Name: ");
		String lname = input.next();
		return lname;
	}
	public int userAccount()
	{
		System.out.print("Enter your account number: ");
		int account;
		account = input.nextInt();
		return account;
	}
 
 
	public void mainMenu()
	{			
		String lName, fName;
		int uA;
		fName = userfName(); 
		lName = userlName(); 
		uA = userAccount();
 
 
		int selection;
		System.out.print("Welcome to the ATM Machine!\n");
		System.out.println("Select from the following menu options below:\n");
		System.out.println("========================");
		System.out.println("| [1]  Check Balance   |");
		System.out.println("| [2]  Withdrawal      |");
		System.out.println("| [3]  Deposit         |");
		System.out.println("| [4]  Exit            |");
        System.out.println("========================");
        System.out.print("Please select your option now: ");
        selection =input.nextInt();
 
		if (selection == 1)
		{
			viewBalance();
		}
		else if (selection == 2)
		{
			withdrawFunds();
		}
		else if (selection == 3)
		{
			depositFunds();
		}
		else if (selection == 4)
		{
			System.out.println("Name:" + fName + " " + lName);
			System.out.println("Account Number:" + uA);
			System.out.println("Current Balance: " + currentBal);
			System.out.println("Thank you for using ATM! \n Goodbye! \n");
		}
	}
	public void viewBalance()
	{
		int selection1;
		System.out.println("You have selected Balance.\n");
		System.out.println("\t-- Your Current Balance is:$ " + currentBal);
		System.out.println("Return to main menu? \n [1] for YES \n");
		selection1 =input.nextInt();
 
		if (selection1 == 1)
		{
			mainMenu();
		}
	}
	public void withdrawFunds() 
	{
		int withdrawSelection;
		System.out.println("Amount to withdraw: ");
		System.out.println("[1] - $20");
		System.out.println("[2] - $40");
		System.out.println("[3] - $50");
		System.out.println("[4] - $100");
		System.out.println("[5] - MAIN MENU");
		System.out.print("Please select your option now: ");
		withdrawSelection =input.nextInt();
 
		if (withdrawSelection == 1)
		{
			accountWithdraw(20);
			mainMenu();
		}	
		else if (withdrawSelection == 2)
		{
			accountWithdraw(40);
			mainMenu();
		}	
		else if (withdrawSelection == 3)
		{
			accountWithdraw(50);
			mainMenu();
		}
		else if (withdrawSelection == 4)
		{
			accountWithdraw(100);
			mainMenu();
		}
		else if (withdrawSelection == 5)
		{
			mainMenu();
		}
	}
	public void accountWithdraw(int withdrawFunds)
	{
		currentBal = currentBal -withdrawFunds - 1.50;
		System.out.println("Please take your funds.");
	}
	public void depositFunds()
	{
		int addSelection;
		System.out.println("Amount to deposit: ");
		System.out.println("[1] - $20");
		System.out.println("[2] - $40");
		System.out.println("[3] - $50");
		System.out.println("[4] - $100");
		System.out.println("[5] - MAIN MENU");
		System.out.print("Please select your option now: ");
		addSelection =input.nextInt();
 
		if (addSelection  == 1)
		{
			accountAdd(20);
			mainMenu();
		}
		else if (addSelection  == 2)
		{
			accountAdd(40);
			mainMenu();
		}
		else if (addSelection  == 3)
		{
			accountAdd(50);
			mainMenu();
		}
		else if (addSelection  == 4)
		{
			accountAdd(100);
			mainMenu();
		}
		else if (addSelection  == 5)
		{
			mainMenu();
		}	
	}
	public void accountAdd (int depositFunds)
	{
		currentBal = currentBal +depositFunds - 1.50;
		System.out.println("Thank you.");
	}
	public static void main(String[] args)
	{
 
    		new Main().mainMenu();  //creating the instance and calling the method
	}
}