Really struggling to get my head around authO management clients so I can update users information. I've created a Next.js API route for the backend but I'm not sure how to actually amend the user's data. I've followed the docs and got to the point below.

API route

The ID params I manually entered to test and my response is an empty JSON object.

The docs don't make it clear what I'm suppose to do in the update user area in.

var ManagementClient = require("auth0").ManagementClient;

export default async (req, res) => {
  var auth0 = new ManagementClient({
    domain: process.env.AUTH0_BASE_URL,
    clientId: process.env.AUTH0_CLIENT_ID,
    clientSecret: process.env.AUTH0_CLIENT_SECRET,
    scope: "read:users update:users",
  });
  var params = { id: "**************************" };
  var metadata = {
    foo: "bar",
  };

  auth0.users.updateAppMetadata(params, metadata, function (err, user) {
    if (err) {
      // Handle error.
    }

    // Updated user.
    console.log(user);
    res.status(200).json({ user });
  });
};

Error:

API resolved without sending a response for /api/authapi, this may result in stalled requests.
   SanitizedError [APIError]: getaddrinfo ENOTFOUND http
   (node:internal/process/task_queues:81:21) {
      statusCode: 'ENOTFOUND',
      requestInfo: { method: 'post', url: '***********' },
      originalError: Error: getaddrinfo ENOTFOUND http
          at GetAddrInfoReqWrap.onlookup [as oncomplete] (node:dns:69:26) {
        errno: -3008,
        code: 'ENOTFOUND',
        syscall: 'getaddrinfo',
        hostname: 'http',
        response: undefined
      }
    }