diff --git a/src/time-and-attendance/modules/expenses/services/expense-upsert.service.ts b/src/time-and-attendance/modules/expenses/services/expense-upsert.service.ts
index 9687bca..d2c4cb7 100644
--- a/src/time-and-attendance/modules/expenses/services/expense-upsert.service.ts
+++ b/src/time-and-attendance/modules/expenses/services/expense-upsert.service.ts
@@ -1,6 +1,6 @@
 
 import { CreateExpenseResult, UpdateExpensePayload, UpdateExpenseResult, DeleteExpenseResult, NormalizedExpense } from "src/time-and-attendance/utils/type.utils";
-import { toDateFromString, toStringFromDate } from "src/time-and-attendance/utils/date-time.utils";
+import { toDateFromString, toStringFromDate, weekStartSunday } from "src/time-and-attendance/utils/date-time.utils";
 import { Injectable, NotFoundException, Req } from "@nestjs/common";
 import { expense_select } from "src/time-and-attendance/utils/selects.utils";
 import { PrismaService } from "src/prisma/prisma.service";
@@ -27,13 +27,16 @@ export class ExpenseUpsertService {
             //normalize strings and dates
             const normed_expense = this.normalizeExpenseDto(dto);
 
+            //finds the timesheet using expense.date
+            const start_date = weekStartSunday(normed_expense.date);
+
             //parse numbers
             const parsed_amount = this.parseOptionalNumber(dto.amount, "amount");
             const parsed_mileage = this.parseOptionalNumber(dto.mileage, "mileage");
             const parsed_attachment = this.parseOptionalNumber(dto.attachment, "attachment");
 
             const timesheet = await this.prisma.timesheets.findFirst({
-                where: { id: dto.timesheet_id, employee_id: employee_id },
+                where: { start_date, employee_id },
                 select: { id: true, employee_id: true },
             });
             if(!timesheet) throw new NotFoundException(`Timesheet with id ${dto.timesheet_id} not found`);