Item is missing in inventory slot after i pick up and delete the item. C#

Helloo, I'm working on a inventory for my game, and i can pick up items that will be put in the inventory. After i pick it up i see the image in the inv, but after deleting the object from the scene i t$$anonymous$$nk the inventory cant find the Item script anymore. so now other items overwrite the previous item. How can i make sure the Slot keeps the original Item?

 public class InventoryManager : MonoBehaviour
 {
     Slot[] slots = new Slot[5];
     
     void Awake()
     {
         for (int i = 0; i < 5; i++)
         {
             slots[i] = GameObject.Find("Slot-"+i).GetComponent<Slot>();
             Debug.Log(i);
         }
     }
 
     public void Add_Item(Item item)
     {
         foreach (var slot in slots)
         {
             if (slot.item == null)
             {
                 slot.item = item;
                 slot.gameObject.GetComponent<Image>().sprite = item.gameObject.GetComponent<Image>().sprite;
                 break;
             }
         }
     }
 }

//Pick up script

     void OnTriggerEnter(Collider col)
     {
         if (col.tag == "Player")
         {
             GameObject.Find("Library").GetComponent<InventoryManager>().Add_Item(item);
             Destroy(gameObject);
         }
     }
 }