IN VS code it is showing Error in signup controller User validation failed

Question

When I am trying to save/create a new document (user) to MongoDB using Mongoose, I am getting the following validation error inspite of providing all the values with proper datatypes:

ValidationError: User validation failed: username: Path username is required.

I am a beginner at Node.JS and MongoDB. Hence I am not able to understand what is going wrong.

I have also added the following modules:

Express Mongo Mongoo

VS Code is showing error in signup controller

User validation failed: password: Path password is required., fullName: Path fullName is required., username: Path username is required., gender: Path gender is required.

I am facing this problem - please help me solve it. I have shared the code I wrote.

auth.controller.js:

import User from "../models/user.model.js";

export const signup = async (req, res) => {
    try {
        const { fullName, username, password, confirmPassword, gender } = req.body;

        if (password !== confirmPassword) {
            return res.status(400).json({ error: "Passwords don't match" });
        }

        const user = await User.findOne({ username });

        if (user) {
            return res.status(400).json({ error: "Username already exists" });
        }

        // HASH PASSWORD HERE

        // https://avatar-placeholder.iran.liara.run/

        const boyProfilePic = `https://avatar.iran.liara.run/public/boy?username=${username}`;
        const girlProfilePic = `https://avatar.iran.liara.run/public/girl?username=${username}`;

        const newUser = new User({
            fullName,
            username,
            gender,
            profilePic: gender === "male" ? boyProfilePic : girlProfilePic,
        });

        await newUser.save();

        res.status(201).json({
                _id: newUser._id,
                fullName: newUser.fullName,
                username: newUser.username,
                profilePic: newUser.profilePic,
        });
        
    } catch (error) {
        console.log("Error in signup controller", error.message);
        res.status(500).json({ error: "Internal Server Error" });
    }
};

export const login = (req ,res) => {
    console.log("login user");
};

export const logout = (req ,res) => {
    console.log("logout user");
};

usermodel.js:

import mongoose from "mongoose";

const userSchema = new mongoose.Schema(
    {
        fullName: {
            type: String,
            required: true,
        },
        username: {
            type: String,
            required: true,
            unique: true,
        },
        password: {
            type: String,
            required: true,
            minlength: 6,
        },
        gender: {
            type: String,
            required: true,
            enum: ["male", "female"],
        },
        profilePic: {
            type: String,
            default: "",
        },
        // createdAt, updatedAt => Member since <createdAt>
    },
    { timestamps: true }
);

const User = mongoose.model("User", userSchema);

export default User;

Please help me solve the problem.