diff --git a/lib/ui/app/upgrade_dialog.dart b/lib/ui/app/upgrade_dialog.dart
index f90f89739..f45ad2c85 100644
--- a/lib/ui/app/upgrade_dialog.dart
+++ b/lib/ui/app/upgrade_dialog.dart
@@ -30,6 +30,8 @@ import 'package:invoiceninja_flutter/utils/localization.dart';
 
 */
 
+import 'package:flutter/material.dart';
+
 class UpgradeDialog extends StatelessWidget {
   const UpgradeDialog({Key key}) : super(key: key);