Sprite changing position when button pressed

If I alter around with a few of the jump values - true/false, the sprite will move position correctly but only once. I am trying to make it so that whenever the button is pressed the sprite will move to the opposing position. Here is my code so far. I have position as 0, 1.85 and position2 as 0, -1.85.

 using UnityEngine;
 using System.Collections;
 
 public class Movement : MonoBehaviour {
     
     bool jump = false;
     public Vector2 position = new Vector2(0, 0);
     public Vector2 position2 = new Vector2(0, 0);
     
     // Use this for initialization
     void Start () {
     }
     
     // Update is called once per frame
     void Update () {
         if(Input.GetKeyDown(KeyCode.Space)) {
             if(jump == false){
                 jump = true;
                 transform.position = position;
             }
             if(jump == true){
                 jump = false; 
                 transform.position = position2;
             }
         }
     }
 }