Creating single instance or multiple instance of service layer in nodejs

Question

I want to know what should I use to expose my service layer for nodejs api What are the pros and cons of using the approach 1 and 2.

app.post("/", (req, res) => {
  // approach 1
  const test = testService.play();

  // approach 2
  const testService = new TestService();
  testService.play();
});

------ testService.js --------

class TestService {
  play() {}
}

// approach 1
module.exports = new TestService();
// approach 2
module.exports = TestService;