my page don't render the HomePage but if i only use

h1 Test HomePage h1

in render it work.

i wanna know where i should fix it or what im doing wrong thanks for help

or you need to see the other file you can tell me

im kinda new to the programming

import React, { Component } from "react";
import { render } from "react-dom";
import HomePage from "./HomePage";
import RoomJoinPage from "./RoomJoinPage";
import CreateRoomPage from "./CreateRoomPage";
export default class App extends Component {
  constructor(props) {
    super(props);
  }

  render() {
    return (
      <div>
        <HomePage/>
      </div>

    );

  }
}

const appDiv = document.getElementById("app");
render(<App />, appDiv);

this is my HomePage Code

import React, { Component } from "react";
import RoomJoinPage from "./RoomJoinPage";
import CreateRoomPage from "./CreateRoomPage";
import {
  BrowserRouter as Router,
  Switch,
  Route,
  Link,
  Redirect,
} from "react-router-dom";

export default class HomePage extends Component {
  constructor(props) {
    super(props);
  }

  render() {
    return (
      <Router>
        <Switch>
          <Route exact path="/">
            <p>This is the home page</p>
          </Route>
          <Route path="/join" component={RoomJoinPage} />
          <Route path="/create" component={CreateRoomPage} />
        </Switch>
      </Router>
    );
  }
}