How to print an array inside of an object in react?

I used Jsonify and I have this code

@app.route("/eu/hostnames")
def nameeu():
    global regionEU
    return jsonify(values = regionEU.serverName)

That returns this

I tried using it in react with this

export const Tab = (params) => {
  const [data, setData] = useState([{}])
    
  useEffect(() => {
    fetch('/eu/hostnames').then(
      response => response.json()
    ).then(data => {
      setData(data)
    })
  }, []);
    
  return (
    <>
      {console.log(data)}
      <header className={TabCSS.card}> 
        <h1 className={TabCSS.title}> {params.region_name} </h1>
        {data.map((item, idx) => {
          return <p className={TabCSS.server} key={idx}>{item}</p>;
        })} 
      </header>
    </>
  );
}
  
export default Tab;

It then outputs this

How do I get this thing working? I think it has something to do with the tab.js code in react. I tried a lot of things but nothing works. Plz help <3

This line is the problem:

return <p className={TabCSS.server} key={idx}>{item}</p>;

You are trying to render an object in your initial case, {}. You also haven't initialized the state to match the data, which is an object with a .values key. This should fix it:

export const Tab = (params) => {
  const [data, setData] = useState({ values: [] })
    
  useEffect(() => {
    fetch('/eu/hostnames').then(
      response => response.json()
    ).then(data => {
      setData(data)
    })
  }, []);
    
  return (
    <>
      {console.log(data)}
      <header className={TabCSS.card}> 
        <h1 className={TabCSS.title}> {params.region_name} </h1>
        {data.values.map((item, idx) => {
          return <p className={TabCSS.server} key={idx}>{item}</p>;
        })} 
      </header>
    </>
  );
}

Instead of:

setData(data);

try using

setData(data.values);

In the response from your API, the "values" array contains the strings you want to display. However, when you set the state using setData(data), you're assigning the entire response object to the state variable, not just the "values" array.