This is what my code looks like:

function Header() {
    const [{ user }, dispatch] = useStateValue();
    const [isLoggedIn, setIsLoggedIn] = useState(false);
    const navigate = useNavigate();
    let buttonHit = false;

    const handleAuth = () =>
    {
        auth.onAuthStateChanged((authUser) => 
        {
            if (authUser)
            {
                console.log("sume else");
                auth.signOut();
            }
            else
            {
                console.log("sum");
                navigate('/Login');
            }  
        });
    }

    return (
        <Navbar className="navbar" bg="dark" variant="dark" expand="lg">
                <Link className="navbar-brand" to='/'><Navbar.Brand>Scythe's Sweet Treats</Navbar.Brand></Link>
                <Navbar.Toggle aria-controls="main-navbar" />
                <Navbar.Collapse id="main-navbar">
                    <Nav className="mr-auto">
                        <Link to='/' className="nav-links">Home</Link>
                        <Link to='/Products' className="nav-links">Products</Link>
                        <Link to='/About' className="nav-links">About</Link>
                        <Link to='/Gallery' className="nav-links">Gallery</Link>
                        <Link to='/ContactUs' className="nav-links">Contact Us</Link>
                    </Nav>
                    <Nav className="ms-auto">
                        {(user) ? user.uid === 'TirT8syQ6jdbaFPTC0So2HLlsie2' ? <Link className="nav-links" to='/Admin'>Admin</Link> : <Link to='#' className="d-none"></Link> : null}
                        <Link className='nav-links' to='#'>Hello, {!user ? 'Guest': user.email}</Link>
                        <Link onclick={() => handleAuth()} to="#" className="nav-links">{user ? 'Sign Out' : 'Sign In'}</Link>
                    </Nav>
                </Navbar.Collapse>
        </Navbar>
    )
}

I've been having the issue that when I login the onclick is fired immediately and logs the user out, so I changed it because I read a stackOverflow with the same problem. But changing it to {function() {handleAuth()} } or {() => {handleAuth()}} or {() => handleAuth()}