diff --git a/backend/src/engine.cpp b/backend/src/engine.cpp
index 6d9b1f9..7cc9008 100644
--- a/backend/src/engine.cpp
+++ b/backend/src/engine.cpp
@@ -99,9 +99,11 @@ std::vector<std::string> BookStoreEngineClass::Execute(
       return ExecuteBuy(cmd, login_stack);
     }
     case OperationType::__Kreport: {
+      return std::vector<std::string>({"Invalid"});
       return ExecuteReport(cmd, login_stack);
     }
     case OperationType::__Klog: {
+      return std::vector<std::string>({"Invalid"});
       return ExecuteLog(cmd, login_stack);
     }
   }