[Vuejs]-React throwing error on using hooks without class name prefix

Based on the code you provide here the expected result is This is app.js 1

Which I have just reproduced like this,

import React,{ Fragment, useState } from "react";

function App(props) {
  const [x,updateX] = useState(1)
  return (
    <Fragment> 
    <h2>This is app.js {x}</h2>
  </Fragment>
);
}

export default App;

if you still facing an error probably need more context to solve it!!
The output I got