Thread: Infinite loop?

Hi guys,

My code freezes in the console after a BookID is input, following the prompt "Enter the bookID of the book you wish to loan out".
Can't spot where I've gone wrong.

Thanks!

public static void issueBook()
    {
        // choose userID to issue to
        Scanner uid = new Scanner(System.in);
        System.out.println("\nEnter the userID of the user you wish to issue a book to:");
 
        int userIDToIssue = uid.nextInt(); // get userID from user input
        System.out.println("UserID taken in by scanner: " + userIDToIssue);
 
        String userToIssueFirstName = "";
        String userToIssueSurname = "";
        String userFullName = userToIssueFirstName + " " + userToIssueSurname;
 
        // find user by ID
        ListIterator<User> findUserID = userStore.listIterator();
        ListIterator<Book> findBookID = bookStore.listIterator();
        boolean userFound = false;
        boolean bookFound = false;
 
        while (findUserID.hasNext() && userFound == false)
        {
            User u = findUserID.next();
 
            if (u.getUserID() == userIDToIssue)
            {
                userFound = true;  // stops while loop
                //code to run:
 
                if (u.booksHeld>=3)
                {
                    System.out.println("The user already has 3 books. They must first return a book to be able to take out another book");
 
                    // Test userFound assignment to true:
                    System.out.println(userFound);
 
                    issueBook();
                } else
                {
                    // issue the book
 
                    // variables:
                    userToIssueFirstName = u.userFirstName;
                    userToIssueSurname = u.userSurname;
 
                    Scanner bid = new Scanner(System.in);
                    System.out.println("\nEnter the bookID of the book you wish to loan out");
 
                    int bookIDToIssue = bid.nextInt();
 
                    // copy userBorrowing name to Book object
                    while (findBookID.hasNext() && bookFound == false)
                    {
                        Book b = findBookID.next();
 
                        if (b.getBookID() == bookIDToIssue)
                        {
                            bookFound = true;   // stops while loop
 
                            // code to run:
                            if (b.onLoan == true)
                                {
                                    System.out.println("This book is currently out on loan. A message will be generated for the current borrowee to notify them that it has been requested by somebody else.");
 
                                    // TODO: export message to text file
                                } else if (b.onLoan == false)
                                {
                                    b.userBorrowingFirstName = userToIssueFirstName; // name of user borrowing the book is set
                                    b.userBorrowingSurname = userToIssueSurname;
 
                                    b.onLoan = true; // book is set to being on loan
                                } 
                            } else
                            {
                                System.out.println("Book does not exist");
                                issueBook();
                            }
                        }
                        }
 
                        u.booksHeld ++; // then update the number of books held - end
                    }
                }
            }