React-Router url path issues

I am trying to do the create note step of the tutorial.

However, my react-router is acting super weird.

Instead of rendering the component, it looks for localhost:8080/notes/main.js and throws a 404 error.
When I try a simple path with no extra slash /notes for example it renders fine.

Here is my Routes.js:

import React from 'react'
import { Route, Switch } from "react-router-dom";
import Home from "./containers/Home";
import Login from "./containers/Login";
import NotFound from "./containers/NotFound";
import Signup from "./containers/Signup";
import NewNote from "./containers/NewNote";

export default function Routes( props ) {
  return (
      <Route path="/" exact component={Home} />
      <Route path="/notes/login" exact component={Login}  />
      <Route exact path="/signup" component={Signup}/>
      <Route exact path="/notes/new" component={NewNote} />
      { /* Finally, catch all unmatched routes */ }
      <Route component={NotFound} />

If you want to see more code and screenshots then this is my StackOverflow post as it’s not easy adding everything his in Discourse.

Btw, are you starting Create React App on port 8080 instead of the default?

I don’t use create-react-app, I have some hefty experience with react and webpack so I built it myself. But yes I’m using 8080 for my port using webpack dev server plugin.
The other routes work just found, just not any nested routes.

Ah I see. I don’t know if I can be of much help. You might have to ask on Stack Overflow?