,setting a game object to the origin

,i made a simple bouncing ball. it bounces off the wall but eventually leaves how do i transform it back to the center?

so far i have come up with this code but i am not sure what to do with it

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class bounds : MonoBehaviour
transform.position == Vector3 ( 0f, ,0 ,0);

You need to assign it to your ball.

It moves your ball to the origin.