I got an error fetching data in production mode (Cursor session id)

I only started using mongodb about a month ago so I’m not sure if this is the right place to ask my question.
When I upload the next js site to varcel I receive this error from time to time

err: Cursor session id (------ - -------=) is not the same as the operation contexts session id (none)

Note (the number of results is approximately 500)
Api Code :slight_smile:

const getBrands = async (req, res) => {
  try {
    const db = (await clientPromise).db();
    const brands = await db.collection("brands").find().toArray();
    res.json({ brands });
  } catch (err) {
    return res.status(500).json({ err: err.message });

connection string :

import { MongoClient } from "mongodb";

const uri = process.env.MONGO_URI;
const options = {
  useUnifiedTopology: true,
  useNewUrlParser: true,

let client;
let clientPromise;

if (!process.env.MONGO_URI) {
  throw new Error("Please add your Mongo URI to .env.local");

if (process.env.NODE_ENV === "development") {
  if (!global._mongoClientPromise) {
    client = new MongoClient(uri, options);
    global._mongoClientPromise = client.connect();
  clientPromise = global._mongoClientPromise;
} else {
  client = new MongoClient(uri, options);
  clientPromise = client.connect();
export default clientPromise;

1 Like

Any solutions? I am facing the same issue

@Il_Chi, check out this related issue with a temporary fix. You’ll find other linked issues there as well.