Mongodb – Buffering Timeout Error (MongooseError: Operation `users.insertOne()` buffering timed out after 10000ms)

Whenever i run my application. I get an error after a few seconds. MongooseError: Operation users.insertOne() buffering timed out after 10000ms

Here is the code i used to connect to the database

const mongoose = require("mongoose");
const express = require("express")
const app = express()


app.use(express.static("views"))
app.use(express.json())
app.use(express.urlencoded({ extended: true }))


mongoose.set("strictQuery", false);
mongoose.connect("mongodb://localhost/newsletter", { useNewUrlParser: true });

const User = require("./User");
// app.use(User)


app.post("/addUser", (req, res, next) => {
    console.log("reqeuest recieved")
    console.log(req.body)

    const name = req.body.name;
    const email = req.body.email;
    saveUser(name, email)

    // Make the user go to the database here
    res.redirect("/")
    next()
})

app.post("/getEmails", (req, res, next) => {
    res.end("im getting emails")
    next()
})

async function saveUser(name, email) { 
    // before adding to the database, see if it already exists
    // if (await User.findOne( { name: name } )){
    //     console.log("not adding to the database")
    //     return;
    // }
    console.log("req recieved")
    const user = await User.create({
        name: name,
        email: email
    })
    await user.save()
    console.log(user);
}

app.listen(3000, () => {
    console.log("Listening")
})```

I called in the scheema after i connected to the databse. I tried using the link that you get from typing mongosh in a command prompt. That works but i want to use the loacl host.