Nav Agent multiple Units problem

Hello everyone.

I got a problem with Nav Agent in Unity 5. Everythink works perfectly well for 4-5 units, but when i select more they act like crazy. I tried to debug and I am sure that everyone gets good target. Don't know if it is important, but this is mobile game.

My navigation script: (I'm also creating animation in target place, that is why GameObject is made there) using UnityEngine; using System.Collections; using System;

public class TouchNavigation : Interaction { private GameObject clickObj; public GameObject Click; public Transform location;

 public float RelaxDistance = 10;
 private NavMeshAgent agent;
 private Vector3 target = Vector3.zero;
 private bool selected = false;
 private bool isActive = false;
 private Vector3 change = Vector3.zero;
 private Vector3 firstTarget = Vector3.zero;
 public Vector3 RotateV = Vector3.zero;
 private bool rotateDone = false;
 private bool isCreated = false;
 private float timesincestart = 0;








 public override void Dselect()
 {
     selected = false;
 }

 public override void Select()
 {
     selected = true;
 }

 public void sendToTarget()
 {
     Debug.Log("Called, target is:  " + target);

     agent.SetDestination(target);
     agent.Resume();
     isActive = true;

 }
 private bool closeto(Vector3 start, Vector3 finish, Vector3 change)
 {

     if ((finish.x > start.x - change.x && finish.x < start.x + change.x) && (finish.y > start.y - change.y && finish.y < start.y + change.y) && (finish.z > start.z - change.z && finish.z < start.z + change.z))
     {
         return true;
     }

     return false;
 }
 void Start()
 {
     clickObj = null;
     agent = GetComponent<NavMeshAgent>();
     change.x = 20;
     change.y = 20;
     change.z = 20;
 }

 // Update is called once per frame
 void Update()
 {
     if (Input.touchCount == 1)
     {

         if (Input.GetTouch(0).phase == TouchPhase.Began && selected)
         {
             timesincestart = Time.time;

             firstTarget = RtsManager.Current.ScreenPointToMapPosition(Input.GetTouch(0).position);
             if (firstTarget == Vector3.zero)
                 return;
             var ray = Camera.main.ScreenPointToRay(Input.GetTouch(0).position);
             RaycastHit hit;
             Physics.Raycast(ray, out hit);
             var interact = hit.transform.GetComponent<Interactive>();
             if (interact != null)
                 return;

             Vector3 clickSpot = firstTarget;
             clickSpot.y = 10;

             if (isCreated == false)
             {

                 clickObj = (GameObject)GameObject.Instantiate(Click, clickSpot, location.rotation);
                 rotateDone = false;
                 isCreated = true;
             }

         }

         if (Input.GetTouch(0).phase == TouchPhase.Ended)
         {
             if (isCreated)
             {
                 Destroy(clickObj);
                 isCreated = false;
                 rotateDone = true;
                 return;
             }

         }
     }
     if (selected == false && isCreated == true)
     {
         Destroy(clickObj);
         isCreated = false;
         rotateDone = true;
         return;
     }
     if (selected && Input.touchCount != 0)
     {
         var tempTarget = RtsManager.Current.ScreenPointToMapPosition(Input.GetTouch(0).position);
         if (tempTarget != Vector3.zero)
         {
             if (rotateDone == false)
             {
                 if (clickObj != null)
                 {
                     clickObj.transform.Rotate(RotateV * Time.deltaTime * 4);
                     clickObj.transform.position = tempTarget;
                 }
             }
             if (!(closeto(firstTarget, tempTarget, change)))
             {
                 Destroy(clickObj);
                 rotateDone = true;
                 isCreated = false;
                 return;
             }
             float timenow = Time.time;
             if (timenow - timesincestart >= 1)
             {
                 rotateDone = true;
                 if (closeto(firstTarget, tempTarget, change))
                 {
                     target = tempTarget;
                     sendToTarget();

                 }
                 else
                 {
                     Destroy(clickObj);
                     rotateDone = true;
                     isCreated = false;
                     return;

                 }
             }

         }
     }

     if (isActive && Vector3.Distance(target, transform.position) < RelaxDistance)
     {

         agent.Stop();
         isActive = false;
     }

 }

}