Whenever I run it on my web browser, I get an error that says “Uncaught error. Failed to fetch” Here’s the code that causes the problem.

    useEffect(() => {
      const fetchTweets = async() => {
      const url = 'http://localhost:3000/tweet';
      const authToken =
        'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ0b2tlbklkIjozNX0.PhYEPigRB0Jpj6uW11-J8roshWrR4rfdfCPiXgS2gig'
      const res = await fetch(url, {
        headers: {
          Authorization: `Bearer ${authToken}`
        },
      })
      if (res.status !== 200){
        console.log('Error fetching the api')
      }
      const data = await res.json()
      console.log(data);
      setTweets(data)
    };

    fetchTweets();
  }, []);

I’ve ensured that the server is running and have even tested that it works with the ThunderClient vsCode extension. Please help.

I went to chatGPT, copilot, youtube… I even initialized CORS in the backend I built but still nothing. I copied notJust.dev youtube’s video on a twitter frontend integrated with the backend. He never got this error but now I do and I can’t resolve it no matter what I try. I even cloned his repo word for word and it still doesn’t work.