diff --git a/include/dbus_monitor.hpp b/include/dbus_monitor.hpp
index aeab103..74d38f6 100644
--- a/include/dbus_monitor.hpp
+++ b/include/dbus_monitor.hpp
@@ -212,8 +212,10 @@
                             conn.close();
                             return;
                         }
-                        std::string ifaceMatchString =
-                            propertiesMatchString + ",arg0='" + interface + "'";
+                        std::string ifaceMatchString = propertiesMatchString;
+                        ifaceMatchString += ",arg0='";
+                        ifaceMatchString += interface;
+                        ifaceMatchString += "'";
                         BMCWEB_LOG_DEBUG << "Creating match "
                                          << ifaceMatchString;
                         thisSession.matches.emplace_back(