Cannot destructure property '_id' of 'req.user' as it is undefined

Question

Doesn't work the request (below) as needed, drops out into an error:

app.get('/protected', auth.isAuthenticated(User), function(req, res) {
    res.send('Hoooora! Authentificated!');
});

The isAuthenticated function is called from the auth.js file:

auth.js:

const SECRET = 'secret-message';

const jwt = require('jsonwebtoken');
const { expressjwt: expressJwt } = require('express-jwt');
const compose = require('composable-middleware');


function sign(user) {
    return jwt.sign({
        _id: user._id,
    }, SECRET, {
        expiresIn: 60 * 60
    });
}

function sendUnauthorized(req, res) {
    console.log(req.headers.authorization);
    console.log(req.user);
    res.status(401).json ({ message: 'Unathorized' });
};


const validateJwt = expressJwt({
    secret: SECRET,
    algorithms: ['HS256'],
    fail: sendUnauthorized,
    getToken(req){
        if(req.headers.authorization && req.headers.authorization.split(' ')[0] === 'Bearer') {
            return req.headers.authorization.split(' ')[1];
        } else if (req.query && req.query.access_token) {
            return req.query.access_token;
        }
    return null;
    }
});


function isAuthenticated(User) {
    console.log('isAuthenticated is called');
    return compose()
        .use(validateJwt)
        .use((req, res, next) => {
            // Attach user to request
            const { _id } = req.user;
            console.log(_id + req.user);
            User.findById(_id, function(err, user) {
                if (err) return next(err);
                if (!user) return sendUnauthorized(req, res);
                req.user = user;
                console.log('Successfuly verified user by token: ');
                next();
            });
        });
};

module.exports = {
    sign,
    sendUnauthorized,
    isAuthenticated,
};

I get an error when the isAuthenticated function runs. And I don't figure out how to fix it:

"error":{"message":"Cannot destructure property '_id' of 'req.user' as it is undefined."

There is a suspicion that the body-parser or express is not working. Although I did yarn add body-parser and yarn add express. In the index.js file code I also added the following:

const express = require('express');
const app = express();
app.use(express.urlencoded({ extended: true }));
app.use(express.json());