Express Session ID changes during every api request for react-native app

Question

I am trying to make requests to my local backend from my react-native app however, whenever I call a new request the session id changes which causes it to fail. I first make a POST request to login which succeeds and returns an object containing my login information. I then try to make a GET request to access the devices page, however my authChecker() function does not recognize the sessionID and sends a 401 error message:

'You have been signed out, please return to the login page'.

I looked into the network tab in my app web page and the values of the session id for my login and devices pages are different (it should be the same).

I already have a functioning local backend and web site however I am trying to create a react app that also uses the backend to display the information on mobile phones. I am using Expo to create my react app and currently I am testing it on the web on http://10.0.10.162:19006.

This is the code in my app that makes requests to the local backend.

import React, { useEffect, useState } from 'react';
import axios from 'axios';

function GetDevices() {
  const [expiredDevices, setExpiredDevices] = useState([]);

  useEffect(() => {
    axios.post('http://localhost:8080/api/login', {
      email: '',
      password: '',
      visitorId: '',
    })
    .then((response) => {
      console.log('The authorization token is: ', response.data.user);
      
      axios.get('http://localhost:8080/api/devices', {
        headers: {
            Authorization: `Bearer ${response.data.user}`,
        }, 
      })
      .then((response) => {
        console.log('Data from axios: ', response.data);
        setExpiredDevices(response.data);
      })
      .catch((error) => {
        console.log(error.response);
      });
    })
    .catch((error) => {
      console.log(error.response);
    });
  }, []);

  return (
    expiredDevices
  );
}
export default GetDevices;

In my app.js for my backend, I have this line which authenticates the user.

app.use('/api/devices', authChecker(true), devicesRouter);

The authChecker() code:

/**
 * @fileoverview middlewares and helpers
 */

// Ensure the user is authenticated, either redirect them to login or return 401 for the frontend
module.exports.authChecker = (backend) => {
  return (req, res, next) => {
    if (!req.session.user) {
      if (backend) {
        res.status(401).send('You have been signed out, please return to the login page');
      } else {
        res.redirect(`/login?redirect=${encodeURIComponent(req.originalUrl)}`);
      }
    } else {
      next();
    }
  };
};

And this is the session value in the network tab: