diff --git a/backend/jobs/scrape_booking_rates.py b/backend/jobs/scrape_booking_rates.py
index 1b74a25..14861ea 100644
--- a/backend/jobs/scrape_booking_rates.py
+++ b/backend/jobs/scrape_booking_rates.py
@@ -69,7 +69,7 @@ def _get_oldest_scraped_dates(db: Session, start: date, end: date, limit: int) -
         text("""
             SELECT s.rate_date::date AS rate_date,
                    MAX(r.scraped_at)  AS last_scraped
-            FROM generate_series(:start::date, :end::date, '1 day'::interval) AS s(rate_date)
+            FROM generate_series(CAST(:start AS date), CAST(:end AS date), INTERVAL '1 day') AS s(rate_date)
             LEFT JOIN booking_com_rates r ON r.rate_date = s.rate_date::date
             GROUP BY s.rate_date
             ORDER BY last_scraped ASC NULLS FIRST