diff --git a/src/pretix/base/services/seating.py b/src/pretix/base/services/seating.py
index 4453e7da42..7e3aaee432 100644
--- a/src/pretix/base/services/seating.py
+++ b/src/pretix/base/services/seating.py
@@ -41,7 +41,7 @@ class SeatProtected(LazyLocaleException):
 def validate_plan_change(event, subevent, plan):
     current_taken_seats = set(
         event.seats.select_related('product').annotate(
-            has_op=Exists(OrderPosition.objects.filter(
+            has_op=Exists(OrderPosition.all.filter(
                 seat=OuterRef('pk'),
                 canceled=False,
             ).exclude(
@@ -65,7 +65,7 @@ def validate_plan_change(event, subevent, plan):
 def generate_seats(event, subevent, plan, mapping, blocked_guids=None):
     current_seats = {}
     for s in event.seats.select_related('product').annotate(
-        has_op=Exists(OrderPosition.objects.filter(
+        has_op=Exists(OrderPosition.all.filter(
             seat=OuterRef('pk'),
             canceled=False,
         ).exclude(
@@ -133,7 +133,7 @@ def generate_seats(event, subevent, plan, mapping, blocked_guids=None):
 
     Seat.objects.bulk_create(create_seats)
     CartPosition.objects.filter(seat__in=[s.pk for s in current_seats.values()]).delete()
-    OrderPosition.objects.filter(
+    OrderPosition.all.filter(
         Q(canceled=True) | Q(order__status=Order.STATUS_CANCELED),
         seat__in=[s.pk for s in current_seats.values()],
     ).update(seat=None)
diff --git a/src/tests/api/test_events.py b/src/tests/api/test_events.py
index f9bca368c4..9fd9c20951 100644
--- a/src/tests/api/test_events.py
+++ b/src/tests/api/test_events.py
@@ -1063,6 +1063,41 @@ def test_remove_seating_forbidden(token_client, organizer, event, item, seatingp
                                     'present in the new plan and is already sold."]}'
 
 
+@pytest.mark.django_db
+def test_remove_seating_canceled_seat(token_client, organizer, event, item, seatingplan, order_position):
+    resp = token_client.patch(
+        '/api/v1/organizers/{}/events/{}/'.format(organizer.slug, event.slug),
+        {
+            "seating_plan": seatingplan.pk,
+            "seat_category_mapping": {
+                "Stalls": item.pk
+            }
+        },
+        format='json'
+    )
+    assert resp.status_code == 200
+    event.refresh_from_db()
+    assert event.seating_plan == seatingplan
+    with scopes_disabled():
+        assert event.seats.count() == 3
+        assert event.seat_category_mappings.count() == 1
+
+        order_position.seat = event.seats.first()
+        order_position.canceled = True
+        order_position.save()
+
+    resp = token_client.patch(
+        '/api/v1/organizers/{}/events/{}/'.format(organizer.slug, event.slug),
+        {
+            "seating_plan": None
+        },
+        format='json'
+    )
+    assert resp.status_code == 200
+    order_position.refresh_from_db()
+    assert order_position.seat is None
+
+
 @pytest.mark.django_db
 def test_no_seating_for_series(token_client, organizer, event, item, seatingplan, order_position):
     event.has_subevents = True