InAppBillingPlugin: Restore from redeemed codes does not work (iOS)

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Bug Information

Version Number of Plugin: 1.1.0.35-beta Device Tested On: Multiple iOS devices Simulator Tested On: - Version of VS: 15.2 (26430.12) Release Version of Xamarin: 2.3.4.247 Versions of other things you are using: Mapsui 1.0.9

Steps to reproduce the Behavior

Redeem multiple an IAP codes on iTunes and try to restore it on the iOS device (does not happend all the time. It happens in 1/20 tries).

Expected Behavior

On restore there should be each product that was redeemed with a code or purchased.

Actual Behavior

The last redeemed code returns multiple times. So if you have a code for “Unlock XY” and one for “Remove Ads” the last redeemed code is returned for each redeemed code. In this case if you redeem “Unlock XY” first and “Remove Ads” than, you got 2x “Remove Ads” on the restore function.

Code snippet

        private async void OnRestorePurchasesCommandExecute()
        {
            try
            {
                ProcessIsRunning = true;
                var restoredProducts = new List<string>();

                var connection = await CrossInAppBilling.Current.ConnectAsync();
                if (!connection)
                {
                    await page.DisplayAlert("Error", "Error while connecting to Store.", "OK");
                    return;
                }

                var purchases = (await CrossInAppBilling.Current.GetPurchasesAsync(ItemType.InAppPurchase, new InAppBillingVerifyPurchase()))?.ToArray();
                if (purchases != null && purchases.Any())
                {
                    foreach (var purchase in purchases)
                    {
                        if (Products.Any(p => p.ID == purchase.ProductId))
                        {
                            context.Send(async c =>
                                {
                                    if (purchase.State == PurchaseState.Purchased || purchase.State == PurchaseState.Restored)
                                    {
                                        var product = Products.First(p => p.ID == purchase.ProductId);
                                        product.Purchased = true;

                                        if (await MarkProductAsPurchased(purchase.ProductId))
                                            restoredProducts.Add(product.Name);
                                    }
                                }, null);
                        }
                        else
                        {
                            await page.DisplayAlert("Error", $"Can not identify product with ID \"{purchase.ProductId}\".", "OK");
                        }
                        
                        if (purchase.ProductId == PurchaseableProduct.ALL_PAGES && (purchase.State == PurchaseState.Purchased || purchase.State == PurchaseState.Restored))
	                    {
		                    foreach (var product in Products.Where(p => p.IsPageUnlock))
			                    context.Send(c => { product.Purchased = true; }, null);
	                    }

                        await DependencyService.Get<IWebclient>().SendPurchaseReportAsync(purchase);
                    }

                    await page.DisplayAlert("Status", restoredProducts.Any() ? $"Products have been successfully restored. {Environment.NewLine}{Environment.NewLine}Restored: {string.Join(", ", restoredProducts)}" : "Products could not be restored.", "OK");
                }
            }
            catch (Exception ex)
            {
                await page.DisplayAlert("Error", ex.Message, "OK");
            }
            finally
            {
                await CrossInAppBilling.Current.DisconnectAsync();
                ProcessIsRunning = false;
            }
        }

Screenshotst

Here is entry in my DB from the PurchaseReport-Method I built. The customer gets 2x the last product he restored. http://puu.sh/wdD3q/55a9cd9e74.png