diff --git a/src/slic3r/GUI/SelectMachine.cpp b/src/slic3r/GUI/SelectMachine.cpp
index 13533cd55c..631972109e 100644
--- a/src/slic3r/GUI/SelectMachine.cpp
+++ b/src/slic3r/GUI/SelectMachine.cpp
@@ -2830,7 +2830,7 @@ void SelectMachineDialog::update_ams_check(MachineObject *obj)
         }
     }
 
-    if (obj->is_enable_np) { m_checkbox_list["use_ams"]->SetValue(true); }
+    if (obj && obj->is_enable_np) { m_checkbox_list["use_ams"]->SetValue(true); }
 }
 
 void SelectMachineDialog::update_show_status()