OnCollisionEneter() does nothing C sharp

hey, im trying to make it so when an object its created anything colliding with it, incouding stuff inside if it are stored in a variable. anyway, i cant even make it so it shows a message when it collides. here is the script im using

 using UnityEngine;
 using System.Collections;
 
 public class generatorScript : MonoBehaviour {
 
 
     
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
         
     }
 
     void OnCollisionEnter (Collision collision) {
             Debug.Log("Something is there");
             if (collision.transform.tag =="Base"){
                 Debug.Log("structure:" + collision.transform.name);
                 Transform structureLink = collision.transform;        
             }    
     }
 }
     

the part that i do not understand is that the objetct to wich this script is attacked is in contact with 3 other objects, anyway when i play the game absolutely nopthing happens. any help is much apreciated.