optimizing the code and implementing singleton

Assets/CustomTools/ObjectPooling/Scripts/ObjectPool/ObjectPooler.cs

@@ -1,7 +1,7 @@
 using System.Collections.Generic;
 using UnityEngine;
 
-public class ObjectPooler : MonoBehaviour
+public class ObjectPooler : SceneSingleton<ObjectPooler>
 {
 
     public Dictionary<PooledObjectType, Queue<GameObject>> PoolDictionary;
@@ -10,13 +10,6 @@ public class ObjectPooler : MonoBehaviour
     private Dictionary<PooledObjectType, int> _poolIndexes = new Dictionary<PooledObjectType, int>();
     private Dictionary<PooledObjectType, Transform> _poolMasters = new Dictionary<PooledObjectType, Transform>();
 
-    public static ObjectPooler Instance;
-
-    private void Awake()
-    {
-        Instance = this;
-    }
-
     private void Start()
     {
         PoolDictionary = new Dictionary<PooledObjectType, Queue<GameObject>>();
@@ -98,17 +91,21 @@ public void Despawn(GameObject obj)
     {
         PooledObjectType tag = obj.GetComponent<IPooledObject>().PoolType;
 
-        if (tag != null)
+        if (tag != null && PoolDictionary.ContainsKey(tag))
         {
+
+
             PoolDictionary[tag].Enqueue(obj);
 
             IPooledObject iPooledObj = obj.GetComponent<IPooledObject>();
             if (iPooledObj != null) iPooledObj.OnObjectDespawn();
             obj.SetActive(false);
+
+
         }
         else
         {
-            Debug.LogWarning("Trying to despawn object which is not pooled !");
+            Debug.LogError("Trying to despawn object which is not pooled !");
         }
 
     }

Assets/CustomTools/Sıngleton/SceneSingleton.cs

@@ -0,0 +1,20 @@
+using UnityEngine;
+
+public class SceneSingleton<T> : MonoBehaviour
+    where T : Component
+{
+    static T s_instance = null;
+
+    public static T Instance
+    {
+        get
+        {
+            if (s_instance == null)
+            {
+                s_instance = Object.FindObjectOfType<T>();
+            }
+
+            return s_instance;
+        }
+    }
+}