fix

// register a new user
router.post('/register', async (req, res) => {
    console.log(req.body);
    const { fullname, email, password, password2 } = req.body;
    const errors = [];

    // check for required fields
    if (!fullname || !email || !password || !password2) {
        errors.push({ message: 'Please fill in all fields!' });
    }

    // check passwords match
    if (password !== password2) {
        errors.push({ message: 'The passwords do not match!' });
    }

    // check if password isn't too short
    if (password.length < 8) {
        errors.push({ message: 'Password must be at least 8 characters long!' });
    }

    if (errors.length > 0) {
        res.render('register', { errors, fullname, email, password, password2 });
    } else {
        // check if user already exists
        let user = await User.findOne({ email: email });
        if (user) {
            errors.push({ message: 'User already exists. Please login.' });  // pass this error to the login page
            // redirect to login page
            res.redirect('/auth/login');
        } else {
            // register new user
            let newUser = new User({ fullname, email, password });
            const response = await newUser.save();
            res.json(response);
        }
    }

});