diff --git a/apps/web/components/booking/pages/BookingPage.tsx b/apps/web/components/booking/pages/BookingPage.tsx
index 0d5f5d059b..a07f30bd3a 100644
--- a/apps/web/components/booking/pages/BookingPage.tsx
+++ b/apps/web/components/booking/pages/BookingPage.tsx
@@ -262,7 +262,8 @@ const BookingPage = ({
       phone: z
         .string()
         .refine((val) => isValidPhoneNumber(val))
-        .optional(),
+        .optional()
+        .nullable(),
       smsReminderNumber: z
         .string()
         .refine((val) => isValidPhoneNumber(val))