diff --git a/powerauth-client-model/src/main/java/com/wultra/security/powerauth/client/model/error/PowerAuthClientException.java b/powerauth-client-model/src/main/java/com/wultra/security/powerauth/client/model/error/PowerAuthClientException.java
index 2ecbbf3a3..8655aa443 100644
--- a/powerauth-client-model/src/main/java/com/wultra/security/powerauth/client/model/error/PowerAuthClientException.java
+++ b/powerauth-client-model/src/main/java/com/wultra/security/powerauth/client/model/error/PowerAuthClientException.java
@@ -18,6 +18,7 @@
 package com.wultra.security.powerauth.client.model.error;
 
 import java.io.Serial;
+import java.util.Optional;
 
 /**
  * PowerAuth client exception.
@@ -29,12 +30,13 @@ public class PowerAuthClientException extends Exception {
     @Serial
     private static final long serialVersionUID = -4721271754602015511L;
 
-    private PowerAuthError powerAuthError;
+    private final PowerAuthError powerAuthError;
 
     /**
      * Default constructor.
      */
     public PowerAuthClientException() {
+        this.powerAuthError = null;
     }
 
     /**
@@ -43,6 +45,7 @@ public PowerAuthClientException() {
      */
     public PowerAuthClientException(String message) {
         super(message);
+        this.powerAuthError = null;
     }
 
     /**
@@ -52,6 +55,7 @@ public PowerAuthClientException(String message) {
      */
     public PowerAuthClientException(String message, Throwable cause) {
         super(message, cause);
+        this.powerAuthError = null;
     }
 
     /**
@@ -69,8 +73,8 @@ public PowerAuthClientException(String message, Throwable cause, PowerAuthError
      * Get the PowerAuth error object.
      * @return PowerAuth error object.
      */
-    public PowerAuthError getPowerAuthError() {
-        return powerAuthError;
+    public Optional<PowerAuthError> getPowerAuthError() {
+        return Optional.ofNullable(powerAuthError);
     }
 
 }
\ No newline at end of file
diff --git a/powerauth-client-model/src/main/java/com/wultra/security/powerauth/client/model/error/PowerAuthError.java b/powerauth-client-model/src/main/java/com/wultra/security/powerauth/client/model/error/PowerAuthError.java
index eca486e43..8f97eceea 100644
--- a/powerauth-client-model/src/main/java/com/wultra/security/powerauth/client/model/error/PowerAuthError.java
+++ b/powerauth-client-model/src/main/java/com/wultra/security/powerauth/client/model/error/PowerAuthError.java
@@ -17,12 +17,18 @@
  */
 package com.wultra.security.powerauth.client.model.error;
 
+import java.io.Serial;
+import java.io.Serializable;
+
 /**
  * Class representing a PowerAuth error.
  *
  * @author Petr Dvorak, petr@wultra.com
  */
-public class PowerAuthError {
+public class PowerAuthError implements Serializable {
+
+    @Serial
+    private static final long serialVersionUID = 3172664961204150558L;
 
     private String code;
     private String message;