--- caldav_handler.rs
+++ caldav_handler.rs
@@ -242,9 +242,9 @@
             }
         },
         None => {
-            (StatusCode::NOT_IMPLEMENTED, Json(json\!({
-                "error": "Calendar service not available"
-            })))
+            let error_dto = CalendarEventDto::default();
+            error\!("Calendar service not available");
+            (StatusCode::NOT_IMPLEMENTED, Json(error_dto))
         }
     }
 }
@@ -277,9 +277,9 @@
             }
         },
         None => {
-            (StatusCode::NOT_IMPLEMENTED, Json(json\!({
-                "error": "Calendar service not available"
-            })))
+            let error_dto = CalendarEventDto::default();
+            error\!("Calendar service not available");
+            (StatusCode::NOT_IMPLEMENTED, Json(error_dto))
         }
     }
 }
@@ -320,9 +320,9 @@
             }
         },
         None => {
-            (StatusCode::NOT_IMPLEMENTED, Json(json\!({
-                "error": "Calendar service not available"
-            })))
+            let error_dto = CalendarEventDto::default();
+            error\!("Calendar service not available");
+            (StatusCode::NOT_IMPLEMENTED, Json(error_dto))
         }
     }
 }