diff --git a/application_form/api/sales/views.py b/application_form/api/sales/views.py
index ea6dc398..366c32a5 100644
--- a/application_form/api/sales/views.py
+++ b/application_form/api/sales/views.py
@@ -57,6 +57,7 @@
     ApplicationTimeNotFinishedException,
 )
 from application_form.services.lottery.machine import distribute_apartments
+from application_form.services.queue import _adjust_positions
 from application_form.services.reservation import (
     transfer_reservation_to_another_customer,
 )
@@ -243,15 +244,38 @@ def set_state(self, request, pk=None):
         queue_position = state_change_event_serializer.validated_data.get(
             "queue_position", None
         )
-        if queue_position is not None:
-            reservation.queue_position = queue_position
+        new_state = state_change_event_serializer.validated_data.get("state")
+
+        if (
+            queue_position is not None
+            and new_state != ApartmentReservationState.CANCELED
+        ):
+            # conver queue_position from string to number
+            if isinstance(queue_position, str):
+                queue_position = int(queue_position.lstrip("0"))
+
+            # position correction in queue
+            _adjust_positions(
+                ApartmentReservation.objects.filter(
+                    apartment_uuid=reservation.apartment_uuid
+                ),
+                "queue_position",
+                queue_position,
+                by=1,
+            )
 
+        # set state and position
         state_change_event = reservation.set_state(
             **state_change_event_serializer.validated_data,
             user=request.user,
         )
 
-        if queue_position is not None:
+        if (
+            queue_position is not None
+            and new_state != ApartmentReservationState.CANCELED
+        ):
+            # save new position to database
+            reservation.queue_position = queue_position
             reservation.save(update_fields=["queue_position"])
 
         return Response(
diff --git a/application_form/models/reservation.py b/application_form/models/reservation.py
index 81427781..b2bc7aa7 100644
--- a/application_form/models/reservation.py
+++ b/application_form/models/reservation.py
@@ -135,6 +135,8 @@ def set_state(
             )
 
         if queue_position is not None:
+            if isinstance(queue_position, str):
+                queue_position = int(queue_position.lstrip("0"))
             self.queue_position = queue_position
 
         state_change_event = ApartmentReservationStateChangeEvent.objects.create(