diff --git a/lib/features/notifications/data/push_registration_service.dart b/lib/features/notifications/data/push_registration_service.dart
index 208330f..114226c 100644
--- a/lib/features/notifications/data/push_registration_service.dart
+++ b/lib/features/notifications/data/push_registration_service.dart
@@ -49,7 +49,9 @@ class FirebasePushRegistrationService implements PushRegistrationService {
     final timezone = await FlutterTimezone.getLocalTimezone();
     await _firestore.collection('users').doc(uid).set({
       'fcmTokens': FieldValue.arrayUnion([token]),
-      'timezone': timezone,
+      // IANA-Kennung, z. B. "Europe/Berlin" – das Objekt selbst ist nicht
+      // Firestore-serialisierbar.
+      'timezone': timezone.identifier,
     }, SetOptions(merge: true));
   }
 
@@ -78,6 +80,12 @@ final pushRegistrationServiceProvider = Provider<PushRegistrationService>((ref)
 final pushSetupProvider = Provider<void>((ref) {
   final user = ref.watch(authStateProvider).value;
   if (user != null) {
-    ref.read(pushRegistrationServiceProvider).registerDevice(user);
+    ref.read(pushRegistrationServiceProvider).registerDevice(user).catchError(
+      (Object error, StackTrace stack) {
+        // Bewusst nur loggen: Push-Registrierung darf den App-Start nie
+        // blockieren, aber Fehler müssen im Log sichtbar sein.
+        debugPrint('Push-Registrierung fehlgeschlagen: $error');
+      },
+    );
   }
 });