diff --git a/src/MaaWpfGui/ViewModels/UI/CopilotViewModel.cs b/src/MaaWpfGui/ViewModels/UI/CopilotViewModel.cs
index 44cfabdaf7..652b8565f7 100644
--- a/src/MaaWpfGui/ViewModels/UI/CopilotViewModel.cs
+++ b/src/MaaWpfGui/ViewModels/UI/CopilotViewModel.cs
@@ -254,7 +254,7 @@ namespace MaaWpfGui.ViewModels.UI
         /// <returns>关卡名 or string.Empty</returns>
         private static string FindStageName(params string[] names)
         {
-            if (((names = names.Where(str => !str.IsNullOrEmpty()).ToArray())?.Length ?? 0) == 0)
+            if ((names = names.Where(str => !str.IsNullOrEmpty()).ToArray()).Length == 0)
             {
                 return string.Empty;
             }