diff --git a/aspnet-core/modules/settings/LINGYUN.Abp.SettingManagement.Application/LINGYUN/Abp/SettingManagement/TimeZoneSettingsAppService.cs b/aspnet-core/modules/settings/LINGYUN.Abp.SettingManagement.Application/LINGYUN/Abp/SettingManagement/TimeZoneSettingsAppService.cs
index b33d06646..e2ce4dbc4 100644
--- a/aspnet-core/modules/settings/LINGYUN.Abp.SettingManagement.Application/LINGYUN/Abp/SettingManagement/TimeZoneSettingsAppService.cs
+++ b/aspnet-core/modules/settings/LINGYUN.Abp.SettingManagement.Application/LINGYUN/Abp/SettingManagement/TimeZoneSettingsAppService.cs
@@ -21,7 +21,7 @@ public class TimeZoneSettingsAppService : SettingManagementAppServiceBase, ITime
     protected ISettingManager SettingManager { get; }
     protected ITimezoneProvider TimezoneProvider { get; }
 
-    internal const string UnspecifiedTimeZone = "Unspecified";
+    private const string UnspecifiedTimeZone = "Unspecified";
 
     public TimeZoneSettingsAppService(ISettingManager settingManager, ITimezoneProvider timezoneProvider)
     {