Playing Audio Source on trigger not working

Im trying to make a song play when the player character passes a collider, but i can't manage to make it posible :c I have been using the ActivatreTrigger Standar Asset and ....

 using System;
 using UnityEngine;
 using Object = UnityEngine.Object;
 
 namespace UnityStandardAssets.Utility
 {
     public class ActivateTrigger : MonoBehaviour
     {
         // A multi-purpose script which causes an action to occur when
         // a trigger collider is entered.
         public enum Mode
         {
             Trigger = 0,    // Just broadcast the action on to the target
             Replace = 1,    // replace target with source
             Activate = 2,   // Activate the target GameObject
             Enable = 3,     // Enable a component
             Animate = 4,    // Start animation on target
             Deactivate = 5  // Decativate target GameObject
         }
 
         public Mode action = Mode.Activate;         // The action to accomplish
         public Object target;                       // The game object to affect. If none, the trigger work on this game object
         public GameObject source;
         public int triggerCount = 1;
         public bool repeatTrigger = false;
 
 
         private void DoActivateTrigger()
         {
             triggerCount--;
 
             if (triggerCount == 0 || repeatTrigger)
             {
                 Object currentTarget = target ?? gameObject;
                 Behaviour targetBehaviour = currentTarget as Behaviour;
                 GameObject targetGameObject = currentTarget as GameObject;
                 if (targetBehaviour != null)
                 {
                     targetGameObject = targetBehaviour.gameObject;
                 }
 
                 switch (action)
                 {
                     case Mode.Trigger:
                         if (targetGameObject != null)
                         {
                             targetGameObject.BroadcastMessage("DoActivateTrigger");
                         }
                         break;
                     case Mode.Replace:
                         if (source != null)
                         {
                             if (targetGameObject != null)
                             {
                                 Instantiate(source, targetGameObject.transform.position,
                                             targetGameObject.transform.rotation);
                                 DestroyObject(targetGameObject);
                             }
                         }
                         break;
                     case Mode.Activate:
                         if (targetGameObject != null)
                         {
                             targetGameObject.SetActive(true);
                         }
                         break;
                     case Mode.Enable:
                         if (targetBehaviour != null)
                         {
                             targetBehaviour.enabled = true;
                         }
                         break;
                     case Mode.Animate:
                         if (targetGameObject != null)
                         {
                             targetGameObject.GetComponent<Animation>().Play();
                         }
                         break;
                     case Mode.Deactivate:
                         if (targetGameObject != null)
                         {
                             targetGameObject.SetActive(false);
                         }
                         break;
                 }
             }
         }
 
 
         private void OnTriggerEnter(Collider other)
         {
             DoActivateTrigger();
 
         }
     }
 }

a script I found online

 using UnityEngine;
 using System.Collections;
 
 public class SoundTrigger : MonoBehaviour {
 
     public AudioSource source;
     public AudioClip clip;
     private bool isPlayed;
 
     void Start(){
         source = GetComponent<AudioSource> ();
         isPlayed = false;
     }
 
     void OntriggerEnter(Collider other){
         if (!isPlayed) {
             source.Play ();
             isPlayed = true;
         }
     }
 
     void OntriggerExit(Collider other){
         if (source.isPlaying) {
             source.Stop ();
         }
     }
 }