How to fetch Authorization header token to logout JWT Flask ReactJs

Question

I'm new to Flask and React.
I'm confused on how I can get the Authorization Token to logout.

On Postman I can Register/login/logout a user just fine. But when it comes to getting the header Authentication 'Bearer' from the frontend I find I'm stuck.

This is what I got so far when trying to fetch the Authorization.

const [ email, setEmail] = useState('')
const [ password, SetPassword] = useState('')

const onSubmitClick = (e) => {
    e.preventDefault()
    console.log('You pressed login')
    let opts = {
        'email': email,
        'password': password
    }
    console.log(opts)
    fetch('/auth/login', {
        method: 'post',
        headers: {
            'Content-Type': 'application/json'
            },  
        body: JSON.stringify(opts)
    }).then(r => r.json())
    .then(token => {
        if (token.auth_token){
            login(token)
            console.log(token)
        }
        else {
            console.log("Please type in the correct Email or Password")
        }
    })
}

const onLogoutClick = (e) => {

    fetch('/auth/login', {
        method: 'post',
        headers: {
            'Authorization': `Basic `,
            'Content-Type': 'application/json'
            },
    }).then(r => r.json())
    .then(token => {
        if (token.auth_token){
            login(token)
            console.log(token)
        }
        else {
            console.log("Please type in the correct Email or Password")
        }
    })
}

Login Api:

class LoginAPI(MethodView):

    def post(self):

        post_data = request.get_json()
        try:

            user = User.query.filter_by(
                email=post_data.get('email')
            ).first()
            if user and bcrypt.check_password_hash(
                user.password, post_data.get('password')
            ):
                auth_token = user.encode_auth_token(user.id)
                if auth_token:
                    responseObject = {
                        'status': 'success',
                        'message': 'Successfully logged in.',
                        'auth_token': auth_token.decode()
                    }
                    return make_response(jsonify(responseObject)), 200
            else:
                responseObject = {
                    'status': 'fail',
                    'message': 'User does not exist.'
                }
                return make_response(jsonify(responseObject)), 404
        except Exception as e:
            print(e)
            responseObject = {
                'status': 'fail',
                'message': 'Try again'
            }
            return make_response(jsonify(responseObject)), 500

Logout Api:

class LogoutAPI(MethodView):

    def post(self):
        
        auth_header = request.headers.get('Authorization')
        if auth_header:
            auth_token = auth_header.split(" ")[1]
        else:
            auth_token = ''
        if auth_token:
            resp = User.decode_auth_token(auth_token)
            if not isinstance(resp, str):
                
                blacklist_token = BlacklistToken(token=auth_token)
                try:
                    
                    db.session.add(blacklist_token)
                    db.session.commit()
                    responseObject = {
                        'status': 'success',
                        'message': 'Successfully logged out.'
                    }
                    return make_response(jsonify(responseObject)), 200
                except Exception as e:
                    responseObject = {
                        'status': 'fail',
                        'message': e
                    }
                    return make_response(jsonify(responseObject)), 200
            else:
                responseObject = {
                    'status': 'fail',
                    'message': resp
                }
                return make_response(jsonify(responseObject)), 401
        else:
            responseObject = {
                'status': 'fail',
                'message': 'Provide a valid auth token.'
            }
            return make_response(jsonify(responseObject)), 403

Being new to reach I really believe I'm a silly mistake somewhere
Postman everything works fine, only problem is frontend logout!
Thanks a lot!