Object will not return to start position after player respawns

Hello, I'm stuck on a part of my code for a object that fly's towards you after you trigger it to. The object has collider on it that is used for a trigger and a child object on it that uses my Respawn Script to reset the player when it touches the object that too has a collider. My question is that I can't make it return to the start position after it made it to it's target position. I know that isDead is not being triggered because there's no condition to tell it to be true if something happens but I can't figure out how I would write it out in code to make it know when the play hits the collider with the Respawn Script on it makes the object go back to it's start position.

Thank You to anyone that helps out.

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class fireWorks : MonoBehaviour {
 
     public Transform target;//Go to this position
     public Transform returnTarget;//Go back to start position
     public float speed;//speed it travels at
     public bool setOff;
     public bool isDead;
     public Respawn myRespawn;
 
     void Start(){
         GameObject.FindWithTag("Firework").GetComponent<Respawn>();
         isDead = false;
     }
 
     void OnTriggerEnter2D(Collider2D other){
         if(other.gameObject.CompareTag("Player")){
             setOff = true;
         }    
     }
 
     void Update(){
         if(setOff){
             float step = speed * Time.deltaTime;
             transform.position = Vector3.MoveTowards(transform.position, target.position, step);
         }
         if(isDead == true){//if dead move back.
             setOff = false;
             float beep = speed * Time.deltaTime;
             transform.position = Vector3.MoveTowards(transform.position, returnTarget.position, beep);
         }
     }
 }