diff --git a/Rs.SkyLine/Flow/LoadAndUnloadTask.cs b/Rs.SkyLine/Flow/LoadAndUnloadTask.cs
index 652581c..190c6a0 100644
--- a/Rs.SkyLine/Flow/LoadAndUnloadTask.cs
+++ b/Rs.SkyLine/Flow/LoadAndUnloadTask.cs
@@ -634,6 +634,7 @@ namespace Rs.MotionPlat.Flow
             List<ActionItem> ais = sm.ActionItems.Where(l => l.Load.Type == TurnoverType.ToBeTested).ToList();
             if (ais != null && ais.Count > 0)
             {
+                TurnoverFlow.Instance.CannotMoveFromTestTrayToTurnoverTray();
                 foreach (ActionItem item in ais)
                 {
                     loadTaskList.Add(ActionItem2TurnoverInfo(sm, item, ETaskType.Load));
@@ -650,6 +651,7 @@ namespace Rs.MotionPlat.Flow
             List<ActionItem> ais = sm.ActionItems.Where(l => l.Load.Type == TurnoverType.Turnover && (l.To.Type != TurnoverType.Turnover && l.To.Type != TurnoverType.Tester)).ToList();
             if (ais != null && ais.Count > 0)
             {
+                TurnoverFlow.Instance.CannotMoveFromTestTrayToTurnoverTray();
                 foreach (ActionItem item in ais)
                 {
                     unloadTaskList.Add(ActionItem2TurnoverInfo(sm, item, ETaskType.Unload));
@@ -666,6 +668,7 @@ namespace Rs.MotionPlat.Flow
             List<ActionItem> ais = sm.ActionItems.Where(l => l.Load.Type == TurnoverType.Turnover && l.To.Type == TurnoverType.Turnover).ToList();
             if(ais!=null&&ais.Count>0)
             {
+                TurnoverFlow.Instance.CannotMoveFromTestTrayToTurnoverTray();
                 foreach (ActionItem item in ais)
                 {
                     changeTaskList.Add(ActionItem2TurnoverInfo(sm, item, ETaskType.Change));