`Problem.find()` buffering timed out after 10000ms in a different node project

I am currently trying to create a discord bot that takes some data from the user and stores it using mongodb atlas. That works fine and when i try to do some database operations like .save() and .find() it works in the main file. But when i try to make another node project and get an access to the database and use .find(), it says : Problem.find() buffering timed out after 10000ms.

Main bot code :

require('dotenv').config()
const express = require('express');
const app = express();
const path = require('path');
const mongoose = require('mongoose')
mongoose.set('strictQuery', false);

app.use(express.json())
app.use(express.urlencoded({ extended : true }));

const uname = process.env.uname;
const password = process.env.password;
const url = `mongodb+srv://${uname}:${password}@panchofridayhai.a9fbhvv.mongodb.net/?retryWrites=true&w=majority`;
const port = process.env.PORT || 8000;
const Problem = require('./models/problems')
const token = process.env.token;

const { Client, IntentsBitField } = require('discord.js');
const problems = require('./models/problems');

const client = new Client({
    intents: [
        IntentsBitField.Flags.Guilds,
        IntentsBitField.Flags.GuildMembers,
        IntentsBitField.Flags.GuildMessages,
        IntentsBitField.Flags.MessageContent
    ]
})

const start = async() => {
    try {
        await mongoose.connect(url);
        app.listen(port, () => {
            let date_object = new Date();
            console.table({status : "running", time : date_object.toLocaleTimeString()});
        });
    } 
    catch(err) {
        console.log(err);
    }
}

start();

function makeid(length) {
    let result = '';
    const characters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
    const charactersLength = characters.length;
    let counter = 0;
    while (counter < length) {
      result += characters.charAt(Math.floor(Math.random() * charactersLength));
      counter += 1;
    }
    return result;
}

client.on('messageCreate', (message) => {
    if(message.author.bot) return;
    message.reply("My name is Mocku, I can prepare mock tests for you.")
})

app.get('/', async (request, response) => {
    const result = await Problem.find();
    response.json({"problems" : result});
})

let id__, already = false;

client.on('interactionCreate', (interaction) => {
    if(interaction.isChatInputCommand()) {
        if(interaction.commandName == "create") {
            if(already) {
                interaction.reply("You restarted the creation process by typing /create again....\nInitializing....")
                id__ = makeid(15);
                return;
            }
            already = true;
            interaction.reply("Initializing....\nType /create to start the process and /add to add a problem\nType /create again to repeat the process")
            id__ = makeid(15);
        }
        if(interaction.commandName === "add") {
            let problemStatement = interaction.options.get('problem_statement').value;
            let option_one = interaction.options.get('option1').value;
            let option_two = interaction.options.get('option2').value;
            let option_three = interaction.options.get('option3').value;
            let option_four = interaction.options.get('option4').value;
            // console.log(problemStatement);
            const newProblem = new Problem({
                id: id__, 
                statement: problemStatement,
                option1: option_one,
                option2: option_two,
                option3: option_three,
                option4:option_four
            })
            newProblem.save();
            interaction.reply("Your problem has been added....");
        }
    }
})

client.login(token);`

This is the main bot code and this code is not giving any errors, i used .find() and it works fine. But i want to use information from the database and use it in a website.

here is the code of another file:

require('dotenv').config();
const express = require('express');
const app = express();
const port = 5000;
const path = require('path');
const mongoose = require('mongoose')
mongoose.set('strictQuery', false);
const Problem = require('../Mocku/models/problems');

const uname = process.env.uname;
const password = process.env.password;
const url = `mongodb+srv://satyam1:[e-mail]/?retryWrites=true&w=majority`;

app.use(express.json())
app.use(express.urlencoded({ extended : true }));

app.get('/', async (request, response) => {
    try {
        const result = await Problem.find();
        response.send({"problems" : result});
    } catch (error) {
        console.log(error);
    }
})

const start = async() => {
    try {
        await mongoose.connect(url);
        console.log("successfully connected to atlas");
        app.listen(port, () => {
            let date_object = new Date();
            console.table({status : "running", time : date_object.toLocaleTimeString()});
        });
    } 
    catch(err) {
        console.log(err);
    }
}

start();

i saw tons of solutions but none of them worked for me. Am i making a stupid mistake ?

I tried to use .find() and .save() in another node project but it says : Problem.find() buffering timed out after 10000ms

also in the second node project i am using the username satyam1 and password is safely generated. This profile is also allowed to connect to that cluster