A* pathfinding generating new path when created new obstacle

Hi, I have small (hope so) problem with generating new path for spawning moobs if I'm creating obstacles in my game. The piece of code is here:

 using UnityEngine;
 using System.Collections;
 
 public class CreateObstacle : MonoBehaviour {
 
     Ray ray;
     RaycastHit hit;
     public GameObject yourObstacle;
     private float yVariableCorrection = 1f;
     int currentObstacles = 0;
     private int PossiblePlace;
     
     EnemyAI[] enemies;
     
     void Awake() {
         enemies = Component.FindObjectsOfType<EnemyAI>() as EnemyAI[];
     }
 
     void Update () {
 
         ray = Camera.main.ScreenPointToRay (Input.mousePosition);
         PossiblePlace = LayerMask.NameToLayer ("PossiblePlace");
 
         if (Input.GetMouseButtonDown (0)) {
             if (Physics.Raycast (ray, out hit)) {
                 if (hit.transform.gameObject.layer == PossiblePlace && GameManager.currentMoney >= GameManager.createdObstacle) {
                     Instantiate (yourObstacle, new Vector3 (hit.point.x, (hit.point.y + yVariableCorrection), hit.point.z), Quaternion.identity);
                     GameManager.currentMoney -= GameManager.createdObstacle;
                     Debug.Log("Money: " + GameManager.currentMoney); 
                     currentObstacles++;
 
                         AstarPath.active.Scan ();
                         foreach (EnemyAI enemy in enemies) {
                             enemy.GetNewPath();
                         }
                     } 
                         else {
                             Debug.Log ("Wrong place or no money");
                         }
                 }
             }
     }
 }

The problem is: if I create obstacle, graph is changing and exclude impossible points from graph <- it works great. But when I want regenerate new path for enemies it now work so well. If enemy is actually spawned his path is not changing and can go through my obstacle, Fresh spawned enemies don't have this problem.

Screen: