CORS error with worker to localhost:3000

Access to fetch at 'https://users-worker.data-well.workers.dev/users' from origin 'http://localhost:3000' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

Access to fetch at 'https://users-worker.data-well.workers.dev/users' from origin 'http://localhost:3000' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

import { Router } from 'itty-router'
import { withContent } from 'itty-router-extras'
import { Prisma, PrismaClient, User } from '@prisma/client/edge'
import { createCors } from 'itty-cors'

// create CORS handlers
const { preflight, corsify } = createCors({ origins: ['*'] })

const prisma = new PrismaClient()
const router = Router()
const headers = {
  'Access-Control-Allow-Origin': '*',
  'Content-type': 'application/json'
}

router.get('/users', async () => {
  const response: User[] = await prisma.user.findMany()
  return new Response(JSON.stringify(response), {
    headers
  })
})

router.get('/users/:id', async ({ params }) => {
  const { id } = params;
  const response = await prisma.user.findUnique({
    where: {
      id
    }
  })

  return new Response(JSON.stringify(response), { headers })
})

router.post('/users', withContent, async ({ content }) => {
  const {id, name, email} = content;
  const response = await prisma.user.create({
    data: {
      id,
      name,
      email
    }
  })
  return new Response(JSON.stringify(response), { headers })
})

router.all('*', preflight) 
router.all('*', () => new Response('Not Found.', { status: 404 }))

addEventListener('fetch', event => {
  event.respondWith(router.handle(event.request),)
})

import { Router } from 'itty-router'
import { withContent } from 'itty-router-extras'
import { Prisma, PrismaClient, User } from '@prisma/client/edge'
import { createCors } from 'itty-cors'

// create CORS handlers
const { preflight, corsify } = createCors({ origins: ['*'] })

const prisma = new PrismaClient()
const router = Router()
const headers = {
  'Access-Control-Allow-Origin': '*',
  'Content-type': 'application/json'
}

router.get('/users', async () => {
  const response: User[] = await prisma.user.findMany()
  return new Response(JSON.stringify(response), {
    headers
  })
})

router.get('/users/:id', async ({ params }) => {
  const { id } = params;
  const response = await prisma.user.findUnique({
    where: {
      id
    }
  })

  return new Response(JSON.stringify(response), { headers })
})

router.post('/users', withContent, async ({ content }) => {
  const {id, name, email} = content;
  const response = await prisma.user.create({
    data: {
      id,
      name,
      email
    }
  })
  return new Response(JSON.stringify(response), { headers })
})

router.all('*', preflight) 
router.all('*', () => new Response('Not Found.', { status: 404 }))

addEventListener('fetch', event => {
  event.respondWith(router.handle(event.request),)
})

    async getUsers(){
      const response = await fetch('https://users-worker.data-well.workers.dev/users', {
        method: 'get',
        headers: { 'Access-Control-Allow-Origin' : '*' }
      });
      this.users = response
    }

    async getUsers(){
      const response = await fetch('https://users-worker.data-well.workers.dev/users', {
        method: 'get',
        headers: { 'Access-Control-Allow-Origin' : '*' }
      });
      this.users = response
    }