diff --git a/.gitignore b/.gitignore
index 456c0dd7..2dbe75c5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,7 +4,7 @@ gen/
 !.idea/codeStyleSettings.xml
 build
 local.properties
-gradle.properties
+#gradle.properties
 .gradle
 *.iml
 .DS_Store
diff --git a/gradle.properties b/gradle.properties
new file mode 100644
index 00000000..6b5ba814
--- /dev/null
+++ b/gradle.properties
@@ -0,0 +1,6 @@
+# Project-wide Gradle settings.
+
+android.useAndroidX=true
+android.enableJetifier=true
+
+
diff --git a/library/src/main/java/com/anjlab/android/iab/v3/BillingProcessor.java b/library/src/main/java/com/anjlab/android/iab/v3/BillingProcessor.java
index 8b757e56..548ec517 100644
--- a/library/src/main/java/com/anjlab/android/iab/v3/BillingProcessor.java
+++ b/library/src/main/java/com/anjlab/android/iab/v3/BillingProcessor.java
@@ -259,6 +259,19 @@ else if (responseCode == BillingClient.BillingResponseCode.ITEM_ALREADY_OWNED)
 						handleItemAlreadyOwned(purchasePayload.split(":")[1]);
 						savePurchasePayload(null);
 					}
+
+					reportBillingError(responseCode, new Throwable(billingResult.getDebugMessage()));
+
+				}
+				else if (responseCode == BillingClient.BillingResponseCode.USER_CANCELED
+						|| responseCode == BillingClient.BillingResponseCode.SERVICE_UNAVAILABLE
+						|| responseCode == BillingClient.BillingResponseCode.BILLING_UNAVAILABLE
+						|| responseCode == BillingClient.BillingResponseCode.ITEM_UNAVAILABLE
+						|| responseCode == BillingClient.BillingResponseCode.DEVELOPER_ERROR
+						|| responseCode == BillingClient.BillingResponseCode.ERROR
+						|| responseCode == BillingClient.BillingResponseCode.ITEM_NOT_OWNED)
+				{
+					reportBillingError(responseCode, new Throwable(billingResult.getDebugMessage()));
 				}
 			}
 		};
diff --git a/library/src/main/java/com/anjlab/android/iab/v3/PurchaseInfo.java b/library/src/main/java/com/anjlab/android/iab/v3/PurchaseInfo.java
index 5464d665..14615366 100644
--- a/library/src/main/java/com/anjlab/android/iab/v3/PurchaseInfo.java
+++ b/library/src/main/java/com/anjlab/android/iab/v3/PurchaseInfo.java
@@ -29,10 +29,6 @@
  * a purchase from the google play store on his own
  * server. An example implementation of how to verify
  * a purchase you can find here:
- * <pre>
- * See <a href="https://github.com/mgoldsborough/google-play-in-app-billing-verification/blob/
- * master/library/GooglePlay/InAppBilling/GooglePlayResponseValidator.php#L64"> here </a>
- * </pre>
  */
 public class PurchaseInfo implements Parcelable
 {
diff --git a/sample/src/com/anjlab/android/iab/v3/sample2/MainActivity.java b/sample/src/com/anjlab/android/iab/v3/sample2/MainActivity.java
index 50e1a56f..4dd1948f 100644
--- a/sample/src/com/anjlab/android/iab/v3/sample2/MainActivity.java
+++ b/sample/src/com/anjlab/android/iab/v3/sample2/MainActivity.java
@@ -39,7 +39,7 @@ public class MainActivity extends Activity {
     // PRODUCT & SUBSCRIPTION IDS
     private static final String PRODUCT_ID = "com.anjlab.test.iab.s2.p5";
     private static final String SUBSCRIPTION_ID = "com.anjlab.test.iab.subs1";
-    private static final String LICENSE_KEY = BuildConfig.licenceKey; // PUT YOUR MERCHANT KEY HERE;
+    private static final String LICENSE_KEY = "THE_KEY"; //BuildConfig.LICENSE_KEY; // PUT YOUR MERCHANT KEY HERE;
     // put your Google merchant id here (as stated in public profile of your Payments Merchant Center)
     // if filled library will provide protection against Freedom alike Play Market simulators
     private static final String MERCHANT_ID=null;