diff --git a/pom.xml b/pom.xml
index 6e95affec..129662a9c 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>com.uid2</groupId>
     <artifactId>uid2-operator</artifactId>
-    <version>5.63.8</version>
+    <version>5.63.10-alpha-283-SNAPSHOT</version>
   
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
diff --git a/src/main/java/com/uid2/operator/store/CloudSyncOptOutStore.java b/src/main/java/com/uid2/operator/store/CloudSyncOptOutStore.java
index ed0a093f4..42aea4588 100644
--- a/src/main/java/com/uid2/operator/store/CloudSyncOptOutStore.java
+++ b/src/main/java/com/uid2/operator/store/CloudSyncOptOutStore.java
@@ -130,7 +130,9 @@ public void addEntry(UserIdentity firstLevelHashIdentity,
             if (ar.failed()) {
                 failure = new Exception(ar.cause());
             } else if (ar.result().statusCode() != 200) {
-                failure = new Exception("optout api http status: " + String.valueOf(ar.result().statusCode()));
+                String responseBody = ar.result().body();
+                failure = new Exception("optout api http status: " + ar.result().statusCode() 
+                    + ", response: " + (responseBody != null ? responseBody : "empty"));
             }
 
             if (failure == null) {
diff --git a/src/main/java/com/uid2/operator/vertx/GenericFailureHandler.java b/src/main/java/com/uid2/operator/vertx/GenericFailureHandler.java
index 855ea1187..8865ba3a6 100644
--- a/src/main/java/com/uid2/operator/vertx/GenericFailureHandler.java
+++ b/src/main/java/com/uid2/operator/vertx/GenericFailureHandler.java
@@ -33,8 +33,14 @@ public void handle(RoutingContext ctx) {
         }
 
         if (!response.ended() && !response.closed()) {
-            response.setStatusCode(statusCode)
-                    .end(EnglishReasonPhraseCatalog.INSTANCE.getReason(statusCode, null));
+            String responseBody;
+            // Include error message for debugging (especially in e2e tests)
+            if (t != null && t.getMessage() != null) {
+                responseBody = EnglishReasonPhraseCatalog.INSTANCE.getReason(statusCode, null) + ": " + t.getMessage();
+            } else {
+                responseBody = EnglishReasonPhraseCatalog.INSTANCE.getReason(statusCode, null);
+            }
+            response.setStatusCode(statusCode).end(responseBody);
         }
     }
 }
diff --git a/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java b/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java
index fd11f4882..affea0188 100644
--- a/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java
+++ b/src/main/java/com/uid2/operator/vertx/UIDOperatorVerticle.java
@@ -1026,7 +1026,9 @@ private Future handleLogoutAsyncV2(RoutingContext rc) {
                     body.put("optout", "OK");
                     ResponseUtil.SuccessV2(rc, body);
                 } else {
-                    rc.fail(500);
+                    String errorMsg = ar.cause() != null ? ar.cause().getMessage() : "Unknown error";
+                    LOGGER.error("Failed to process logout request: " + errorMsg, ar.cause());
+                    rc.fail(500, ar.cause());
                 }
                 promise.complete();
             });