Native IAP Promo With Monetization SDK 3.0

I wanted to integrate Native IAP Promo with Monetization SDK.
I have done all setup according to this
https://unityads.unity3d.com/help/monetization/placements

But i getting issue while creating Unity Promo Adapter of type PromoAdPlacementContent
https://unityads.unity3d.com/help/beta/native-promo

I have created "iappromoplacement" for iap promo
and also started one Promotions with one iap product

Below is the code that how i am initializing Monetization, basically first i init Unity IAP then after i init Monetization

i am getting error
PromoAdPlacementContent promoContent = Monetization.GetPlacementContent("iappromoplacement") as PromoAdPlacementContent;
INativePromoAdapter adapter = Monetization.CreateNativePromoAdapter (promoContent);

I also checked that placement is ready or not with
Monetization.IsReady("iappromoplacement") but it always return false.

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using UnityEngine.Monetization;
5.  
6. public class UnityAdsManager : MonoBehaviour
7. {
8.     public UnityIAPManager iapManager;
9.     public UnityIAPAdapter iapAdapter;
10.    
11.     string gameId = "1234";
12.     bool testMode = false;
13.    
14.     // Use this for initialization
15.     void Start ()
16.     {
17.         StartCoroutine(InitAds());
18.     }
19.    
20.     public void ShowVideoAd () {
21.         StartCoroutine (ShowVideoAdWhenReady ());
22.     }
23.    
24.     public void ShowRewardedVideoAd () {
25.         StartCoroutine (ShowRewardedVideoAdWhenReady ());
26.     }
27.  
28.     public void InitPromoPlacements()
29.     {
30.         StartCoroutine(InitPromoPlacementsWhenReady());
31.     }
32.  
33.     private IEnumerator InitAds()
34.     {
35.         while (!iapManager.isInit) {
36.             yield return new WaitForSeconds(0.25f);
37.         }
38.         Monetization.SetPurchasingAdapter(iapAdapter);
39.         Monetization.Initialize (gameId, testMode);
40.     }
41.  
42.     private IEnumerator InitPromoPlacementsWhenReady()
43.     {
44.        yield return null;
45.  
46.         PromoAdPlacementContent promoContent = Monetization.GetPlacementContent ("iappromoplacement") as PromoAdPlacementContent;
47.         INativePromoAdapter adapter = Monetization.CreateNativePromoAdapter (promoContent);
48.         Debug.Log("Promo Placement : " + promoContent + " : " + (promoContent == null));
49.     }
50.  
51.     private IEnumerator ShowVideoAdWhenReady()
52.     {
53.         while (!Monetization.IsReady ("video")) {
54.             yield return new WaitForSeconds(0.25f);
55.         }
56.  
57.         ShowAdPlacementContent ad = null;
58.         ad = Monetization.GetPlacementContent ("video") as ShowAdPlacementContent;
59.         Debug.Log("Promo Placement Ready : " + ad);
60.         if(ad != null) {
61.             ad.Show ();
62.         }
63.     }
64.  
65.     private IEnumerator ShowRewardedVideoAdWhenReady()
66.     {
67.         while (!Monetization.IsReady ("rewardedVideo")) {
68.             yield return null;
69.         }
70.  
71.         ShowAdPlacementContent ad = null;
72.         ad = Monetization.GetPlacementContent ("rewardedVideo") as ShowAdPlacementContent;
73.  
74.         Debug.Log("Promo Placement Ready : " + ad);
75.         if (ad != null) {
76.             ad.Show (AdFinished);
77.         }
78.     }
79.    
80.     void AdFinished (ShowResult result) {
81.         if (result == ShowResult.Finished) {
82.             // Reward the player
83.             Debug.Log("Rewarded Video Ad Finished");
84.         }
85.     }
86. }
87.  

 

i faced this issue too i think Native IAP Promo with Monetization still unstable