Receiving `MongooseError: Operation `users.insertOne()` buffering timed out after 10000ms`

I'm trying to store data to my MongoDB server, I wanted started of by trying to add a User data when a new user joins a server, but I keep getting buffered timeout. I've been looking for a solution for a whole day and nothing is working.

Here are some information:

I have whitelisted my ip in the atlas:

My Atlas Network Access

The connection code being used:

mongoose.connect(dbUrl, {
      useNewUrlParser: true,
      useUnifiedTopology: true,
      useFindAndModify: false,
    })
    .then(() => console.log("Database connected!")).catch(err => console.log(err));

My User Model:

const mongoose = require("mongoose");

const UserSchema = new mongoose.Schema({
  userID: { type: String },
  guildID: { type: String },
  xp: { type: Number, default: 0 },
  level: { type: Number, default: 0 },
  balance: {type: Number, default: 0},
  banned: {type: Boolean, default: false},
  muted: {type: Boolean, default: false},
  messages: {type: Number, default: 0},
  lastUpdated: { type: Date, default: new Date() },
});

module.exports = mongoose.model('User', UserSchema);

My Mongo Connection

MONGO_URI=mongodb+srv://<username>:<password>!@personalcluster.rav32vj.mongodb.net/KingsData?retryWrites=true&w=majority

On User Join

const client = require('../index.js')
const levels = require('../models/Users')
const dotenv = require('dotenv')
dotenv.config()

client.on('guildMemberAdd', async (member) => {
    const newUser = new levels({
        userID: member.id,
        guildID: process.env.GUILDID
    });
      
    await newUser.save().catch(e => console.log(`Failed to create user: ${e}`))
})