diff --git a/NumLib/Assembler/SerialExecutor.h b/NumLib/Assembler/SerialExecutor.h
index 18dc2f759e5eef828e870b8f7c9b2490c45b960c..122ca8b34f786ed7c01675e6f6a9a214b0eb70c1 100644
--- a/NumLib/Assembler/SerialExecutor.h
+++ b/NumLib/Assembler/SerialExecutor.h
@@ -166,7 +166,7 @@ struct SerialExecutor
         for (std::size_t i = 0; i < active_container_ids.size(); i++)
         {
             ((*container[active_container_ids[i]]).*method)(
-                i, std::forward<Args>(args)...);
+                active_container_ids[i], std::forward<Args>(args)...);
         }
     }