When my player dies and i hit revive button i want my player back to the game but i m unable to do that please help.

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

public class PlayerMotor : MonoBehaviour {

 private const float LANE_DISTANCE = 2.5f;
 private const float TURN_SPEED = 0.05f;


 // Audio 
 public AudioClip playerHurt;

 AudioSource playerAS;

 //
 private bool isRunning = false;

 // Animation
 private Animator anim;

// Movement private CharacterController controller; private float jumpForce = 4.0f; private float gravity = 12.0f; private float verticalVelocity; private int desiredLane = 1; // 0 = left, 1 = Middle, 2 = Right

 // Speed Modifier
 private float originalSpeed = 8.0f;
 private float speed;
 private float speedIncreaseLastTick;
 private float speedIncreaseTime = 2.5f;
 private float speedIncreaseAmount = 0.1f;

 private void Start()
 {
     speed = originalSpeed;
     controller = GetComponent<CharacterController>();
     anim = GetComponent<Animator>();
     playerAS = GetComponent<AudioSource>();
 }

 private void Update()
 {
     if(!isRunning)
         return;

     if(Time.time - speedIncreaseLastTick > speedIncreaseTime)
     {
         speedIncreaseLastTick = Time.time;
         speed += speedIncreaseAmount;
         GameManager.Instance.UpdateModifier(speed - originalSpeed);
     }


     // Gather the inputs on which lane we should be
     if(MobileInput.Instance.SwipeLeft)
         MoveLane(false);
     if(MobileInput.Instance.SwipeRight)
         MoveLane(true);

     // Calculate where we should be in the future
     Vector3 targetPosition = transform.position.z * Vector3.forward;
     if (desiredLane == 0)
         targetPosition += Vector3.left * LANE_DISTANCE;
     else if (desiredLane == 2)
         targetPosition += Vector3.right * LANE_DISTANCE;

     // Let's calculate our move delta
     Vector3 moveVector = Vector3.zero;
     moveVector.x = (targetPosition - transform.position).normalized.x * speed;

     bool isGrounded = IsGrounded();
     anim.SetBool("Grounded", isGrounded);

     // Calculate Y
     if(isGrounded) // if Grounded
     {
         verticalVelocity = -0.1f;


         if(MobileInput.Instance.SwipeUp)
         {
             // Jump
             anim.SetTrigger("Jump");
             verticalVelocity = jumpForce;
         }
         else if(MobileInput.Instance.SwipeDown)
         {
             // Slide
             StartSliding();
             Invoke("StopSliding", 1.0f);
         }
     }
     else
     {
         verticalVelocity -= (gravity * Time.deltaTime);

         // Fast Falling mechanic
         if(MobileInput.Instance.SwipeDown)
         {
             verticalVelocity = -jumpForce;
         }
     }

     moveVector.y = verticalVelocity;
     moveVector.z = speed;

     // Move the Pengu
     controller.Move(moveVector * Time.deltaTime);

     // Rotate the pengu to where he is going
     Vector3 dir = controller.velocity;
     if (dir != Vector3.zero)
     {
         dir.y = 0;
         transform.forward = Vector3.Lerp(transform.forward,dir, TURN_SPEED);

     }

 }

 private void StartSliding()
 {
     anim.SetBool("Sliding", true);
     controller.height /= 2;
     controller.center = new Vector3(controller.center.x,controller.center.y /2, controller.center.z);
 }

 private void StopSliding()
 {
     anim.SetBool("Sliding", false);
     controller.height *= 2;
     controller.center = new Vector3(controller.center.x,controller.center.y *2, controller.center.z);
 }

 private void MoveLane(bool goingRight){

     // Going Left
     if(!goingRight)
     {
         desiredLane--;
         if (desiredLane == -1)
             desiredLane = 0;
     }
     else
     {
         desiredLane++;
         if(desiredLane == 3)
             desiredLane = 2;
     }
 }

 private bool IsGrounded()
 {
     Ray groundRay = new Ray(
         new Vector3(controller.bounds.center.x,(controller.bounds.center.y - controller.bounds.extents.y) + 0.2f, 
             controller.bounds.center.z),
         Vector3.down);
     Debug.DrawRay(groundRay.origin, groundRay.direction,Color.cyan,1.0f);

     return Physics.Raycast(groundRay, 0.2f + 0.1f);
         
 }

 public void StartRunning() 
 {
     isRunning = true;
     anim.SetTrigger("StartRunning");


 }

 private void Crash()
 {
     anim.SetTrigger("Death");
     isRunning = false;
     playerAS.clip = playerHurt;
     playerAS.PlayOneShot(playerHurt);
     GameManager.Instance.OnDeath();
 }

 private void OnControllerColliderHit(ControllerColliderHit hit)
 {
     switch(hit.gameObject.tag)
     {
         case "Obstacle":
         Crash();
         break;
     }


 }

}