diff --git a/biscuit/apps/alsijil/views.py b/biscuit/apps/alsijil/views.py
index 58c5730a2f5da68daf605191fbabde6041deefec..7d78a9354f4de75eb2d6a4113308da4a19ede421 100644
--- a/biscuit/apps/alsijil/views.py
+++ b/biscuit/apps/alsijil/views.py
@@ -110,8 +110,8 @@ def group_week(request: HttpRequest, year: Optional[int] = None, week: Optional[
                 week=wanted_week.week
             ))
         ).filter(
-            lesson__date_start__lte=wanted_week[0] + timedelta(days=1) * F('lesson__weekday') - 1,
-            lesson__date_end__gte=wanted_week[0] + timedelta(days=1) * F('lesson__weekday') - 1
+            lesson__date_start__lte=wanted_week[0] + timedelta(days=1) * F('weekday') - 1,
+            lesson__date_end__gte=wanted_week[0] + timedelta(days=1) * F('weekday') - 1
         ).select_related(
             'lesson', 'lesson__subject', 'period', 'room'
         ).prefetch_related(