Empty list from in-app purchase

i use in-app purchase for ios, i follow those instructions :
and this code :

import { InAppPurchase } from '@ionic-native/in-app-purchase/ngx';

const FOURCARDS_PRODUCTS = '4cards'; 

export class myPage implements OnInit {
  constructor(private iap: InAppPurchase) {    
        .then((products) => {
          this.productsApp = products;
        .catch((err) => {

but productsApp is still empty, i have setup tax profile and everything is ok. i have deploy my app via test flight but nothing works, any ideas?
in this variable FOURCARDS_PRODUCTS i have add also : com.myapp.4cards
with same results

has anyone manage to work with ionic in-app purchase? thanks