在我的'/about‘代码中，当主页工作时，路由不起作用

<Route path="/about" component={AboutPage} />

import { BrowserRouter as Router, Route, Switch } from 'react-router-dom';

function App() {
  return (
    <Router>
      <Switch>
        <Route exact path="/" component={HomePage} />
        <Route path="/about" component={AboutPage} />
      </Switch>
    </Router>
  );
}

import { Link } from 'react-router-dom';

function HomePage() {
  return (
    <div>
      <h1>Home Page</h1>
      <Link to="/about">Go to About Page</Link>
    </div>
  );
}