testing the rewarded video unity ads

Below i am giving the codes for my unity ads script. i have made "life" as text in my scene which records the number of lives my player has. irrespective of the number of lives he might have i want to make a button which if pressed will show my rewarded ad and after watching it it shall reward the player with 5 coins. problem is , the "life" counter is in a separate script and am not sure, because even though the button if pressed shows a custom ad in "test"mode, but am not sure if the codes work! i should mention that this is the last mile bottleneck after making a complete app.kindly help me.

using System.Collections; using System.Collections.Generic; using UnityEngine; using UnityEngine.Advertisements;

public class unityad : MonoBehaviour { public int lifeleft;

 // Use this for initialization
 void Start () {
     
 



     GameObject lifeobject = GameObject.Find("life");
     UImanager ui = lifeobject.GetComponent<UImanager>();
     lifeleft = ui.life;
     lifeleft = lifeleft + 5;








     
 }
 
 // Update is called once per frame
 void Update () {

     

     
     
 }

 public void showad(){

     if(Advertisement.IsReady()){
         Advertisement.Show ();

     }
 }

 public void HandleAdResult(ShowResult result){
     switch (result) {

     case ShowResult.Finished:
         

         
         
         Debug.Log ("ad finished");
         break;

         

         

     
     


     case ShowResult.Skipped:
         Debug.Log("ad skipped");
         break;

     case ShowResult.Failed:
         Debug.Log("ad failed");
         break;

     }
     
 }

}