PostUserRegistration: Script generated an unhandled asynchronous exception

I can run this without problem in the in the editor, but when I create a new user through the Auth0 dashboard, it doesn’t work. All I get in Logs is a Warning: ExtensibilityImplementationError on post-user-registration: Script generated an unhandled asynchronous exception.

Here’s my hook code:

var request = require('request@2.82.0');

module.exports = function (user, context, cb) {

const url = 'https://url-where-I-post-my-user';
  method: 'POST', 
  url: url, 
  json: true,
  body: {
      "user_id": user.user_id, 
      "username": user.username, 
      "role": user.app_metadata.role,
      "first_name": user.app_metadata.first_name,
      "last_name": user.app_metadata.last_name
  function(error, response, body) { 
    cb(error, response)