Unable to Connect to the MongoDB Database

Using the MongoDb and Mongoose for the first time to store the data of my app.js file. When I run the app.js then it throws this error after a while -> MongooseError: Operation peoples.insertOne() buffering timed out after 10000ms.

import mongoose from "mongoose";

mongoose.set("strictQuery", false);
mongoose.connect(
  "mongodb://localhost:27017/peopleDB",
  { useNewUrlParser: true },
  (err) => {
    if (err) console.log(err);
    else console.log("MongoDB is connected");
  }
);

const peopleSchema = new mongoose.Schema({
  name: String,
  age: Number,
});

const People = new mongoose.model("People", peopleSchema);

const people = new People({ name: "John", age: 37 });

people.save();

this is the code that I wrote