diff --git a/Schaad.Accounting.UI/Components/Pages/Dialogs/TransactionDialog.razor b/Schaad.Accounting.UI/Components/Pages/Dialogs/TransactionDialog.razor
index 427959a..801950b 100644
--- a/Schaad.Accounting.UI/Components/Pages/Dialogs/TransactionDialog.razor
+++ b/Schaad.Accounting.UI/Components/Pages/Dialogs/TransactionDialog.razor
@@ -56,6 +56,7 @@
         Abbrechen
     </FluentButton>
     <FluentButton Appearance="Appearance.Accent"
+                  Disabled="@(SelectedValue is null)"
                   OnClick="@SaveAsync">
         Speichern
     </FluentButton>
diff --git a/Schaad.Accounting.UI/Components/Pages/Dialogs/TransactionDialog.razor.cs b/Schaad.Accounting.UI/Components/Pages/Dialogs/TransactionDialog.razor.cs
index 2bdc942..9268a26 100644
--- a/Schaad.Accounting.UI/Components/Pages/Dialogs/TransactionDialog.razor.cs
+++ b/Schaad.Accounting.UI/Components/Pages/Dialogs/TransactionDialog.razor.cs
@@ -34,10 +34,14 @@ public partial class TransactionDialog : ComponentBase
 
     private async Task SaveAsync()
     {
+        if (editContext is null || SelectedValue is null)
+        {
+            return;
+        }
         if (editContext.Validate())
         {
-            Content.ValueDate = SelectedValue!.Value;
-            Content.BookingDate = SelectedValue!.Value;
+            Content.ValueDate = SelectedValue.Value;
+            Content.BookingDate = SelectedValue.Value;
             await transactionRepository.SaveTransactionAsync(Content);
             await Dialog.CloseAsync(Content);
         }