Fix previous_live_lesson in SchoolSchedule

apps/school/models.py

@@ -59,7 +59,7 @@ class SchoolSchedule(models.Model):
         now_time = now()
         live_lesson = LiveLesson.objects.filter(
             date__week_day=self.weekday % 7 + 1,
-            date__range=[(now_time - timedelta(days=7)).date(), now_time.date()],
+            date__range=[(now_time - timedelta(days=8)).date(), now_time.date()],
             deactivated_at__isnull=True,
         ).first()
         return live_lesson