diff --git a/CHANGELOG.md b/CHANGELOG.md
index ecf08f0..fa9690f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,9 @@
 # Changelog
 All notable changes to this project will be documented in this file.
 
+## [3.1.20]
+- Added `MerchantErrorMessage` and `MerchantErrorCode` fields to `Transaction` in API response, exposing the failure reason and error code for failed/declined payments.
+
 ## [3.1.19]
 - Changed `CardType` values for the `CardInformation` `Type` element to the BIN interchange group classifications: `Consumer Credit`, `Consumer Debit`, `Corporate Credit`, `Corporate Debit`.
 
diff --git a/build.gradle b/build.gradle
index 0ded102..a3cb3d2 100644
--- a/build.gradle
+++ b/build.gradle
@@ -9,7 +9,7 @@ plugins {
 }
 
 group = 'com.altapay'
-version = '3.1.19'
+version = '3.1.20'
 
 repositories {
     mavenCentral()
diff --git a/readme.md b/readme.md
index 1577e4b..b1139a8 100644
--- a/readme.md
+++ b/readme.md
@@ -49,12 +49,12 @@ For integrating Java projects with the AltaPay gateway.
     <dependency>
         <groupId>com.altapay</groupId>
         <artifactId>sdk-java</artifactId>
-        <version>3.1.19</version>
+        <version>3.1.20</version>
     </dependency>
 
 ### Gradle
 
-    implementation 'com.altapay:sdk-java:3.1.18'
+    implementation 'com.altapay:sdk-java:3.1.20'
 
 ## Changelog
 
diff --git a/src/main/resources/xsd/APIResponse.xsd b/src/main/resources/xsd/APIResponse.xsd
index 45f04a2..7f62a22 100644
--- a/src/main/resources/xsd/APIResponse.xsd
+++ b/src/main/resources/xsd/APIResponse.xsd
@@ -481,6 +481,8 @@
             <xs:element name="Terminal" type="xs:string"/>
             <xs:element name="TransactionStatus" type="xs:string"/>
             <xs:element name="ReasonCode" type="xs:string"/>
+            <xs:element name="MerchantErrorMessage" type="xs:string" maxOccurs="1" minOccurs="0"/>
+            <xs:element name="MerchantErrorCode" type="xs:string" maxOccurs="1" minOccurs="0"/>
             <xs:element name="CardHolderMessageMustBeShown" type="xs:boolean" maxOccurs="1" minOccurs="0"/>
             <xs:element name="MerchantCurrency">
                 <xs:simpleType>