diff --git a/backend/src/main/java/service/ConfigExecutorService.java b/backend/src/main/java/service/ConfigExecutorService.java
index d046375..7a64299 100644
--- a/backend/src/main/java/service/ConfigExecutorService.java
+++ b/backend/src/main/java/service/ConfigExecutorService.java
@@ -8,6 +8,7 @@ import java.util.Date;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
+import java.util.stream.Collectors;
 
 import com.google.gson.Gson;
 import com.google.gson.reflect.TypeToken;
@@ -81,13 +82,18 @@ public class ConfigExecutorService {
     catch (HttpClientErrorException e) {
 
       if (e.getStatusCode() == HttpStatus.BAD_REQUEST) {
-        Map<String, String> responseMap = new Gson().fromJson(e.getResponseBodyAsString(),
-            new TypeToken<Map<String, String>>() {
+        Map<String, Object> responseMap = new Gson().fromJson(e.getResponseBodyAsString(),
+            new TypeToken<Map<String, Object>>() {
             }.getType()
         );
 
-        String details = responseMap.get("details");
-        throw new ConfigExecutorException(details);
+        @SuppressWarnings("unchecked")
+        Map<String, String> details = (Map<String, String>) responseMap.get("details");
+        String detailsStr = details.entrySet()
+            .stream()
+            .map(entry -> entry.getKey() + " : " + entry.getValue())
+            .collect(Collectors.joining("\n"));
+        throw new ConfigExecutorException(detailsStr);
       }
       else {
         throw new RuntimeException(