Problem with animator control

I have created an animation control for a simple character. first idle state and then jump.

following the script

using UnityEngine; using System.Collections;

public class AlexiaControls : MonoBehaviour {

 static Animator anim;
 // Use this for initialization
 void Start () {
     anim = GetComponent<Animator>();
 }
 
 // Update is called once per frame
 void Update () {
     if (Input.GetButtonDown("Jump"))
     {
         anim.SetTrigger("isJumping");
     }
 }

}

the problem is, when I run this , and press spcaebar for long jump, after jumping my character comes back to its original position instead of remaining to its new position after jumping

can anybody help ?