react js unable to retrive return data

I use async/await to retrieve a json object and want to get one of the key's value, but it return as undefined. Did I miss something in the code?

  const [registerResponse, setRegisterResponse] = useState({duplicateUser: false, 
         registration: false, username: ''})

  const submitHandler = async(e) => {
    e.preventDefault();
    // console.log(newuser)
    const result = await fetch(API_URL,postOptions);
    setRegisterResponse(result.json())
    console.log(registerResponse)
  }
   console.log(registerResponse.duplicateUser)

I attached the output from developer tool