admin pages in Next js that only authorized users

Question

I have admin pages in Next js that only authorized users should have access to. I have a cookie verification service:

import { NextApiRequest } from 'next'
import { unsign } from './signature'
import db from '../../prisma'

export default async function checkCookie (req: NextApiRequest) {
    const token = req.cookies['sid']
    if (token) {
        const sessionToken = unsign(token, process.env.SECRET!)
        if (sessionToken && typeof sessionToken === 'string') {
            const session = await db.session.findUnique({ where: { sessionToken }, 
                include: { admin: true } })
            if (session) {
                return { admin: session.admin }
            }
        }
    }
}

where should this service be located ?

import { NextPage } from "next"
import TableService  from "../../src/component/TableService"
import AdminLayout from "../../src/component/admin/AdminLayout"
import TableTradeIn from "../../src/component/TableTradeIn"
import checkCookie from "../../src/services/checkCookie"


const  AdminTable: NextPage = (checkCookie) => {
    return (
      <>
        <AdminLayout title="Admin">
          <TableService />
          <TableTradeIn />
        </AdminLayout>
      </>
    )
  }
  
  export default AdminTable

But in this place ('checkCookie' is declared but its value is never read.)