Proxy error: Could not proxy request /time from localhost:3000 to http://localhost:5000

Question

I am working on a simple React-Flask App which aims to fetch the current time from the Back-end and display it on the Front-end.

I have the Flask Back-end and the React Front-end both running together at the same time.

The back-end is working perfectly fine on port 5000:

Back-end

Fetch call '/time' from the front-end is unable to fetch the current time even tho I have my proxy defined in the package.json:

  "proxy": "http://localhost:5000"

Front-end:

function App() {
  const [currentTime, setCurrentTime] = useState(0);

  const getCurrentTime = async (API) => {
    const response = await fetch(API);
    const jsonData = await response.json();
    setCurrentTime(jsonData.time);
    console.log(jsonData);
  };

  useEffect(() => {
    // getCurrentTime('http://localhost:5000/time');
    getCurrentTime('/time');
  }, []);

I have tried the methods discussed here. But none of them seems to work for me.