diff --git a/hb_server/apps/mtm/serializers.py b/hb_server/apps/mtm/serializers.py
index 081dc49..d512b57 100644
--- a/hb_server/apps/mtm/serializers.py
+++ b/hb_server/apps/mtm/serializers.py
@@ -17,8 +17,8 @@ class MaterialDetailSerializer(serializers.ModelSerializer):
         fields = '__all__'
     
     def get_processes_(self, obj):
-        steps = UsedStep.objects.filter(subproduction__product=obj)
-        objs = Process.objects.filter(step_process__in=steps).order_by('number')
+        steps = UsedStep.objects.filter(subproduction__product=obj).values_list('step', flat=True)
+        objs = Process.objects.filter(step_process__id__in=steps).order_by('number')
         return ProcessSimpleSerializer(instance=objs, many=True).data