How to fix Converting circular structure to JSON error - mysql

Question

I'm working on a project for my portfolio and decided I would do the registration page and backend first so that can be out of the way. I followed a tutorial with nodejs and mysql but I'm getting an error saying TypeError: Converting circular structure to JSON --> starting at object with constructor 'HTMLInputElement' | property '__reactFiber$g76m1cpwrsr' -> object with constructor 'FiberNode' --- property 'stateNode' closes the circle. I can't tell exactly where is error might be originating from or what is causing this issue. Any help would be appreciated
Registration page
import React, { useState } from "react";
import "../Styling/Register.css";
import axios from "axios";
function Register() {
const [userName, setUsername] = useState("");
const [userEmail, setUserEmail] = useState("");
const [userPassword, setUserPassword] = useState("");
const [userSubject, setUserSubject] = useState("");
const [account_type, setAcc_Type] = useState("");
const create_user = () => {
axios
.post("http://localhost:3001/register", {
userID: 1001,
userName: userName,
Email: userEmail,
password: userPassword,
subject: userSubject,
acc_type: account_type,
})
.then((res) => {
console.log(res);
})
.catch((err) => {
console.log(err);
});
};
return (
<div className="form">
<input
type="text"
placeholder="FULL NAME"
onChange={(e) => setUsername(e.target.value)}
/>
<input
type="text"
placeholder="Email"
onChange={(e) => setUserEmail(e.target.value)}
/>
<input
type="text"
placeholder="Password"
onChange={(e) => setUserPassword(e.target.value)}
/>
<input
type="text"
placeholder="Field/Subject"
onChange={(e) => setUserSubject(e.target.value)}
/>
<input
type="text"
placeholder="Tutor/Student"
onChange={(e) => setAcc_Type(e.target.value)}
/>
<button onClick={create_user}>Register</button>
</div>
);
}
export default Register;
My server side script in nodejs
const express = require('express');
const mysql = require('mysql');
const cors = require('cors');
const app = express();
app.use(express.json())
app.use(cors());
const db = mysql.createConnection({
host: 'localhost',
user: 'root',
password: '',
database: 'tutor_locator'
});
app.post('/register', (req, res) => {
const userID = req.body.userID;
const userName = req.body.userName;
const Email = req.body.userEmail;
const password = req.body.userPassword;
const subject = req.body.userSubject;
const acc_type = req.body.account_type;
db.query(
'INSERT INTO users(User_ID, User_Name, User_Email, user_Password, User_Subject, Accout_Type) VALUES (?,?,?,?,?,?)',
[userID, userName, Email, password, subject, acc_type],
(err, result) => {
console.log(res);
}
)
})
app.listen(3001, () => {
console.log('server started');
});