diff --git a/DM_Weight/ViewModels/UseAccountWindowViewModel.cs b/DM_Weight/ViewModels/UseAccountWindowViewModel.cs
index 979ccb4..fb19bf2 100644
--- a/DM_Weight/ViewModels/UseAccountWindowViewModel.cs
+++ b/DM_Weight/ViewModels/UseAccountWindowViewModel.cs
@@ -14,7 +14,7 @@ using System.Threading.Tasks;
 
 namespace DM_Weight.ViewModels
 {
-    public class UseAccountWindowViewModel:BindableBase,INavigationAware
+    public class UseAccountWindowViewModel : BindableBase, INavigationAware
     {
         private DateTime? _startDate = new DateTime(DateTime.Now.Year, DateTime.Now.Month, DateTime.Now.Day);
 
@@ -93,7 +93,7 @@ namespace DM_Weight.ViewModels
         }
 
         public void OnNavigatedFrom(NavigationContext navigationContext)
-        { 
+        {
         }
 
         /// <summary>
@@ -103,7 +103,7 @@ namespace DM_Weight.ViewModels
         {
             get => new DelegateCommand(() =>
             {
-                GridReportUtil.UserAccount(StartDate, EndDate, User.Nickname ?? "");
+                GridReportUtil.UserAccount(StartDate, EndDate, User == null ? "" : User.Nickname);
 
             });
         }