I keep getting errors ShoppingCart.js:16  GET http://localhost:5001/api/cart net::ERR_CONNECTION_REFUSED and signup.js:71 POST http://localhost:5001/api/users/register net::ERR_CONNECTION_REFUSED. Im unsure what the issue is. I spent hours doing reasarch but I cant find the solution. It gives me the same type of error when i signup aswell so I assume its one big mistake i made thats affecting it all. The error occurs when I do a signup, login and when i access the shopping cart which makes me believe its a backend issue of some sort.

import { useState } from "react";
import axios from "axios";

function Login() {
    const [loginEmail, setLoginEmail] = useState('');
    const [loginPassword, setLoginPassword] = useState('');
    const [loginError, setLoginError] = useState({
        loginEmail: '',
        loginPassword: '',
        general: ''
    });
    const [loading, setLoading] = useState(false);

    const handleLoginEmailChange = (e) => {
        setLoginEmail(e.target.value);
        setLoginError(prevErrors => ({ ...prevErrors, loginEmail: e.target.value ? '' : 'Email is required' }));
    };

    const handleLoginPasswordChange = (e) => {
        setLoginPassword(e.target.value);
        setLoginError(prevErrors => ({ ...prevErrors, loginPassword: e.target.value ? '' : 'Password is required' }));
    };

    const handleLoginSubmit = async (e) => {
        e.preventDefault();
        if (!loginEmail || !loginPassword) {
            setLoginError(prevErrors => ({
                ...prevErrors,
                loginEmail: !loginEmail ? 'Email is required' : '',
                loginPassword: !loginPassword ? 'Password is required' : '',
            }));
            return;
        }

        setLoading(true);
        try {
            const response = await axios.post('http://localhost:5001/api/users/login', { email: loginEmail, password: loginPassword });
            console.log('Login successful:', response.data);

            if (response.data.token) {
                console.log('Token received:', response.data.token);
                localStorage.setItem("token", response.data.token);
                console.log('Token stored in localStorage:', localStorage.getItem('token'));
                window.location.href = '/';
            } else {
                setLoginError(prevErrors => ({ ...prevErrors, general: 'No token received from server.' }));
            }
        } catch (error) {
            console.log('Error during login:', error);
            setLoginError(prevErrors => ({ ...prevErrors, general: `Login failed: ${error.response?.data?.message || 'Please try again.'}` }));
        } finally {
            setLoading(false);
        }
    };

    return (
        <div>
            <form className="login-sheet" onSubmit={handleLoginSubmit}>
                <label>
                    Email:
                    <input type="text" value={loginEmail} onChange={handleLoginEmailChange} aria-invalid={loginError.loginEmail ? "true" : "false"} aria-describedby="loginEmailError" />
                    {loginError.loginEmail && <p id="loginEmailError" className="error">{loginError.loginEmail}</p>}
                </label>
                <label>
                    Password:
                    <input type="password" value={loginPassword} onChange={handleLoginPasswordChange} aria-invalid={loginError.loginPassword ? "true" : "false"} aria-describedby="loginPasswordError" />
                    {loginError.loginPassword && <p id="loginPasswordError" className="error">{loginError.loginPassword}</p>}
                </label>
                <button type="submit" disabled={loading}>{loading ? 'Submitting...' : 'Submit'}</button>
                {loginError.general && <p className="error">{loginError.general}</p>}
            </form>
        </div>
    );
}

export default Login;

import { useState, useEffect } from "react";
import axios from "axios";

function Cart() {
    const [cart, setCart] = useState([]);
    const [error, setError] = useState('');
    const [loading, setLoading] = useState(false);

    useEffect(() => {
        const fetchCart = async () => {
            setLoading(true);
            try {
                const token = localStorage.getItem('token');
                const config = { headers: { 'Authorization': `Bearer ${token}` } };
                const response = await axios.get('http://localhost:5001/api/cart', config);
                setCart(response.data.items);
            } catch (error) {
                setError('Error fetching cart');
            } finally {
                setLoading(false);
            }
        };
        fetchCart();
    }, []);

    const handleAddItem = async (productId, quantity) => {
        try {
            const token = localStorage.getItem('token');
            const config = { headers: { 'Authorization': `Bearer ${token}` } };
            await axios.post('http://localhost:5001/api/cart/add', { productId, quantity }, config);
            const response = await axios.get('http://localhost:5001/api/cart', config);
            setCart(response.data.items);
        } catch (error) {
            setError('Error adding item');
        }
    };

    const handleRemoveItem = async (productId) => {
        try {
            const token = localStorage.getItem('token');
            const config = { headers: { 'Authorization': `Bearer ${token}` } };
            await axios.delete(`http://localhost:5001/api/cart/remove/${productId}`, config);
            const response = await axios.get('http://localhost:5001/api/cart', config);
            setCart(response.data.items);
        } catch (error) {
            setError('Error removing item');
        }
    };

    return (
        <div>
            <h1>Shopping Cart</h1>
            {loading && <p>Loading...</p>}
            {error && <p className="error">{error}</p>}
            <ul>
                {cart.map(item => (
                    <li key={item.productId._id}>
                        <h2>{item.productId.name}</h2>
                        <p>Quantity: {item.quantity}</p>
                        <button onClick={() => handleRemoveItem(item.productId._id)}>Remove</button>
                    </li>
                ))}
            </ul>
        </div>
    );
}

export default Cart;

const mongoose = require('mongoose');

const cartSchema = new mongoose.Schema({
    userId: { type: mongoose.Schema.Types.ObjectId, ref: 'User', required: true },
    items: [
        {
            productId: { type: mongoose.Schema.Types.ObjectId, ref: 'Product', required: true },
            quantity: { type: Number, required: true, min: 1 },
        }
    ]
});

const Cart = mongoose.model('Cart', cartSchema);

module.exports = Cart;

const jwt = require('jsonwebtoken');

function auth(req, res, next) {
    const token = req.header('Authorization')?.replace('Bearer ', '');
    console.log('Received Token:', token);

    if (!token) {
        return res.status(401).json({ message: 'No token, authorization denied' });
    }

    try {
        const decoded = jwt.verify(token, process.env.JWT_SECRET);
        req.user = { userId: decoded.userId, role: decoded.role };
        next();
    } catch (err) {
        res.status(401).json({ message: 'Token is not valid' });
    }
}

module.exports = auth;

import { findOne } from "../models/User";

// User login
router.post('/login', async (req, res) => {
    const { email, password } = req.body;

    try {
        const user = await findOne({ email });
        if (!user) {
            return res.status(400).json({ message: 'Invalid credentials' });
        }

        const isMatch = await bcrypt.compare(password, user.password);
        if (!isMatch) {
            return res.status(400).json({ message: 'Invalid credentials' });
        }

        const token = jwt.sign({ userId: user._id }, process.env.JWT_SECRET, { expiresIn: '1h' });
        res.json({ token });
    } catch (err) {
        res.status(500).json({ message: err.message });
    }
});

Ive been researching this problem for hours and cant figure it out. the error pops up for all things i do on my website. When i signup login and access the shopping cart.