Having an issue with getting a register/ login form to work on HTML using localStorage. As part of my assignment, I cannot use databases or php even though these are easier. Specifically the issue is occurring during my submit function.

The syntax error coming back is Identifier registerUser has already been declared, and highlights const reponse = processUser (username.value, password.value) in the console.

Here's my JavaScript code:

//setup form

window.addEventListener(DOMContentLoaded, setupForm);



function setupForm() {

    const form = document.getElementById(login);

    form.addEventListener(submit, handleSubmit);

}



//handle Submit

function handleSubmit(event) {

    event.preventDefault();



    const {

        Username,

        Password,

        login_type,

        result

    } = event.target;



    const processUser = login_type.value == register ? registerUser : loginUser;

    const response = processUser(username.value, password.value);

    result.innerHTML = response;

}



//register new user

function registerUser(username, password) {

    window.localStorage.setItem(username, username);

    window.localStorage.setItem(password, password);



    return 'New user ${username} now registered!';

}



//login existing user

function loginUser(username, password) {

    const registeredUser = window.localStorage.getItem(username, username);

    const registeredUser = window.localStorage.getItem(password, password);



    const validUser = username == registeredUser;

    const validPassword = password == registeredUser;



    if (validUser && validPassword) {

        return 'User ${username} successfully logged-in!';

    }

    //error form for incorrect username or password

    else if (!validUser) return 'Incorrect username or password';

}

HTML form:

<fieldset>

    <form id=login action=submit method=post>

        <legend><b>Login here!</b></legend><br />

        <div>

            <label for=username>Username:</label>

            <input id=username type=text name=username required />

        </div>

        <div>

            <label for=password>Password:</label>

            <input id=password type=password name=Password required />

        </div>

</fieldset>

<span>

    <input id=login type=hidden name=login_type value=login checked=checked></input>

    <!--Hidden for the purposes of my script working-->

    <input type=submit value=Submit /><br /><br />

    <output name=result></output>

    </fieldset>

</span>

Any help would be greatly appreciated as this is very frustrating!