Drag and drop with collider

Hi all. My problem is simple. I can drag and drop an item in my scene.But the problem is that my object can't collider with others objects. I don't want my object crosses others. Thank you.

Here my code:

 using UnityEngine;
 using System.Collections;
 
 
 public class fee : MonoBehaviour {
 
     private Vector3 pos;
     public bool vole = true  ;
     private Vector3 screenPos;
     private Vector3 currentScreenPos;
     private Vector3 currentPos;
     private Vector3 lastPosition;
     private Vector3 lastPos;
     private Vector3 offset;
     private Vector3 dir;
     public float moveSpeed;
     private CharacterController controller;
     
     void Start () {
     
     }
     
 
     void Update(){
             MoveUpdate();
     }
     
     void MoveUpdate(){   
         
         
         if(vole){
             if (Application.platform == RuntimePlatform.Android){
             
                 pos = Camera.main.ScreenToWorldPoint(new Vector3(Input.GetTouch(0).position.x, Input.GetTouch(0).position.y, 0));
             }
             else{
             
                 pos = Camera.main.ScreenToWorldPoint(new Vector3(Input.mousePosition.x, Input.mousePosition.y, 0));
                 lastPos = pos;
             }
         }
          
         if (Input.touchCount == 1) {    
 
             Touch f0 = Input.GetTouch(0);
             Ray ray = Camera.main.ScreenPointToRay(Input.GetTouch(0).position);
             RaycastHit hit;
 
             if (Physics.Raycast (ray, out hit, 100)) {
                 //On vérifie que l'on clique bien sur la fée     
                 if(hit.collider.tag == "Fee"){
                   if (f0.phase == TouchPhase.Began) {
                         screenPos = Camera.main.WorldToScreenPoint(transform.position);
                         offset = transform.position - Camera.main.ScreenToWorldPoint(new Vector3(f0.position.x, f0.position.y, 0));   
                     }else if(f0.phase == TouchPhase.Moved){
                             
                         currentScreenPos = new Vector3(f0.position.x, f0.position.y,0);
                         currentPos = Camera.main.ScreenToWorldPoint(currentScreenPos) + offset;
                         transform.position = currentPos;
                         lastPosition = currentPos;
                     }
                 }
             }
             
                 
             
                 
         } 
         
         
 
     }
     
     void OnMouseDrag() {
          transform.position = new Vector3(pos.x,pos.y,0);    
     }
     
     void OnCollisionEnter(Collision collision)
     {
         StartCoroutine("collisionFee");
         
     }
     /*
       void OnTriggerEnter(Collider other) {
       
             StartCoroutine("collisionFee");
         
     }
     */
      IEnumerator collisionFee() {
         vole = false;
         transform.position = lastPosition;
         transform.position = new Vector3(lastPos.x,lastPos.y,0);
         yield return new WaitForSeconds(1f);
         vole = true;
     }
 
 }