diff --git a/server/routers/booking/output.ts b/server/routers/booking/output.ts
index 4fb2bf8f7..a0845d0c2 100644
--- a/server/routers/booking/output.ts
+++ b/server/routers/booking/output.ts
@@ -3,6 +3,7 @@ import { z } from "zod"
 import { ChildBedTypeEnum } from "@/constants/booking"
 
 import { phoneValidator } from "@/utils/zod/phoneValidator"
+import { nullableStringValidator } from "@/utils/zod/stringValidator"
 
 // MUTATION
 export const createBookingSchema = z
@@ -126,13 +127,12 @@ const rateDefinitionSchema = z.object({
 const linkedReservationsSchema = z.object({
   confirmationNumber: z.string().default(""),
   hotelId: z.string().default(""),
-  checkInDate: z.string().datetime(),
-  checkOutDate: z.string().datetime(),
-  cancellationNumber: z.string().default(""),
+  checkinDate: z.string(),
+  checkoutDate: z.string(),
+  cancellationNumber: nullableStringValidator,
   roomTypeCode: z.string().default(""),
   adults: z.number().int(),
   children: z.number().int(),
-  guaranteeCode: z.array(z.string()).default([]),
   profileId: z.string().default(""),
 })