From a00fd280900bd7d5295a887e5688e72d94732577 Mon Sep 17 00:00:00 2001
From: James Montemagno <james.montemagno@gmail.com>
Date: Tue, 24 Apr 2018 09:21:57 -0700
Subject: [PATCH] Fixes #140

---
 src/Plugin.InAppBilling.Android/InAppBillingImplementation.cs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Plugin.InAppBilling.Android/InAppBillingImplementation.cs b/src/Plugin.InAppBilling.Android/InAppBillingImplementation.cs
index bba0f20..fece0ac 100644
--- a/src/Plugin.InAppBilling.Android/InAppBillingImplementation.cs
+++ b/src/Plugin.InAppBilling.Android/InAppBillingImplementation.cs
@@ -347,7 +347,7 @@ async Task<Purchase> PurchaseAsync(string productSku, string itemType, string pa
             {
                 var purchases = await GetPurchasesAsync(itemType, verifyPurchase);
 
-                var purchase = purchases.FirstOrDefault(p => p.ProductId == productSku && payload.Equals(p.DeveloperPayload));
+                var purchase = purchases.FirstOrDefault(p => p.ProductId == productSku && payload.Equals(p.DeveloperPayload ?? string.Empty));
 
                 return purchase;
             }
@@ -355,7 +355,7 @@ async Task<Purchase> PurchaseAsync(string productSku, string itemType, string pa
             if (verifyPurchase == null || await verifyPurchase.VerifyPurchase(data, sign))
             {
                 var purchase = JsonConvert.DeserializeObject<Purchase>(data);
-                if (purchase.ProductId == productSku && payload.Equals(purchase.DeveloperPayload))
+                if (purchase.ProductId == productSku && payload.Equals(purchase.DeveloperPayload ?? string.Empty))
                     return purchase;
             }