The above error occurred in the component

Im getting this issue when i add the switch tag, so far i think i have not mixed up any tags but iam not understanding where exactly i have made the error

please help me resolve this issue for this code im getting this error
im new to react js pls help me solve this issue

import "regenerator-runtime/runtime";
import React from "react";
import { login, logout } from "./utils";
import "./global.css";
import "bootstrap/dist/css/bootstrap.min.css";
import { Container, Navbar, Nav, NavDropdown } from "react-bootstrap";
import { BrowserRouter as Router, Switch, Route, Link } from "react-router-dom";

// components
import Home from "./Components/Home";
import NewPoll from "./Components/NewPoll";
import PollingStation from "./Components/PollingStation";


import getConfig from "./config";
const { networkId } = getConfig(process.env.NODE_ENV || "development");

export default function App() {
  return (
    <Router>
      <Navbar collapseOnSelect expand='lg' bg='dark' variant='dark'>
        <Container>
          <Navbar.Brand href='/'>
            VoteBlocks
          </Navbar.Brand>
          <Navbar.Toggle aria-controls='responsive-navbar-nav' />
          <Navbar.Collapse id='responsive-navbar-nav'>
            <Nav className='mx-auto'></Nav>
            <Nav>
              <Nav.Link href='/NewPoll'>New Poll</Nav.Link>
              <Nav.Link onClick={window.accountId === "" ? login : logout}>
                {window.accountId === "" ? "Login" : window.accountId}
              </Nav.Link>
            </Nav>
          </Navbar.Collapse>
        </Container>
      </Navbar>

      <Switch>

        <Route exact path='/'>
          <Home />
        </Route>

        <Route exact path='/PollingStation'>
          <PollingStation />
        </Route>

        <Route exact path='/NewPoll'>
          <NewPoll />
        </Route>

      </Switch>

    </Router>
  );
}