When using the `auth` wrapper or session in route handlers, it is returning as undefined

[Honey0908]

I want to make secure role based API , but in route.ts file session comes as undefined

 import { auth } from '@/auth';
  import { currentUser } from '@/lib/auth';
  import { db } from '@/lib/db';
  import {  NextResponse } from 'next/server';

  export const POST = auth(async (req) => {
    const user = await currentUser();
    console.log(user) // undefined
    // if user.role is admin then fetch the data 
    const { shopId } = await req.json();
    const products = await db.product.findMany({
      where: {
        shopId,
      },
    });
    return NextResponse.json({
      products,
    });
  });