diff --git a/src/entity_manager/entity_manager.hpp b/src/entity_manager/entity_manager.hpp
index 636a904..fdcce53 100644
--- a/src/entity_manager/entity_manager.hpp
+++ b/src/entity_manager/entity_manager.hpp
@@ -80,6 +80,7 @@
 
     bool propertiesChangedInProgress = false;
     boost::asio::steady_timer propertiesChangedTimer;
+    size_t propertiesChangedInstance = 0;
 
     void startRemovedTimer(boost::asio::steady_timer& timer,
                            nlohmann::json& systemConfiguration);