diff --git a/Modbus.Net/ModBus.Net/FBox/SignalRConnector.cs b/Modbus.Net/ModBus.Net/FBox/SignalRConnector.cs
index ff27b0e..f0ec5ed 100644
--- a/Modbus.Net/ModBus.Net/FBox/SignalRConnector.cs
+++ b/Modbus.Net/ModBus.Net/FBox/SignalRConnector.cs
@@ -421,6 +421,7 @@ namespace ModBus.Net.FBox
                                     _groupNameBoxUid.Clear();
                                     _machineData.Clear();
                                     _machineDataType.Clear();
+                                    _boxUidBoxNo.Clear();
                                 }
                             }
                             _connected = false;