Deleting odd number in queue list

public class queueLinked<i> {
    private Node rear;
    private Node front;
    private int siz;


    public boolean isEmpty() {//function return boolean if is empty or not
        boolean response = false;
        if (siz == 0) {
            response = true;

        }
        return response;
    }

    public void enqueue(int element) { // inserting the value type of int
        Node node = new Node(element);
        if (front == null) {
            rear = node;
            front = node;

        } else {
            rear.setNext(node);
            rear = node;
            siz++;
        }

    }

    public queueLinked() {
        front = null;
        rear = null;
        siz = 0;
    }

    public Node dequeue() { // to remove the a element in the queue
        Node response = null;
        if (front != null) ;
        if (front.getNext() != null) {
            response = new Node(front.getData());
            front = front.getNext();
            siz--;
        } else {
            response = new Node(front.getData());
            front = null;
            rear = null;
        }
        return response;
    }

    public Node peak() {
        Node response = null;
        if (!isEmpty()) {
            response = new Node(front.getData());
        }
        return response;
    }

    public int getSiz() { // to get the size
        return siz;
    }

    public void display() { // display the queue function
        System.out.print("\nQueue = ");
        if (siz == 0) {
            System.out.print("Empty\n");
            return;
        }
        Node ptr = front;
        while (ptr != rear.getNext()) {
            System.out.print(ptr.getData() + " ");
            ptr = ptr.getNext();
        }
        System.out.println();
    }


    public void deleteOdd() {
        if (siz == 0) {
            System.out.print("Empty\n");
            return;
        }
        Node ptr = front;
        Node tmp ;

        while (ptr != rear  ) {

            if (ptr.getData() % 2 != 0) {
                  tmp = ptr.getNext();
                ptr.data = tmp.getData();
                ptr.next = tmp.next;
            }

            else
                ptr = ptr.getNext();


        }
        System.out.println();
    }

}

Queue = 1 2 3 4 2 1 

out but after deleting odd

Queue = 2 4 2 1