What is the problem when using BrowserRouter and getting 404 error?

Question

React

Hello! Point me to the right path, I beg you.
There is a project .
Used HashRouter to route my application. Everything would be fine, but the lattice in the url began to strain. I changed it to BrowserRouter, besides, the specifics of the application are similar to the situation when, judging by the titorial , it is necessary to use the BrowserRouter (a dynamic application with asynchronous requests to a third-party API).
The root element looks like this:

<Provider store={store}>
    <BrowserRouter basename={"/"}>
      <App />
    </BrowserRouter>
  </Provider>

router looks like this:

<Switch>
            <Route exact path="/" component={Menu}/>
            <Route path="/delivery" component={Delivery} />
            <Route path="/pay" component={Pay} />
            <Route path="/about" component={About} />
            <Route path="/manager" component={Manager} />
            <Route path="/personal" component={Personal} />
            <Route component={NotFound} />
          </Switch>

So, having redone it, I got the following: I go through the default route "/" everything is ok. I reboot the page - everything is ok. Then I go along the "/delivery" route - everything is ok. Reboot page - 404 error. And so it is with the rest. When you try to get to the site, for example, at so-dev.tk/delivery , the same thing happens. When you try to register the route manually on the command line - the same 404 error. In fact, routes are only available through programmatic interaction (links). With HashRouter everything works perfectly.
I could leave HashRouter as well, but it became extremely interesting why BrowserRouter behaves this way. On local, by the way, BrowserRouter works well.
Thanks in advance for your replies.