Getting net::ERR_ABORTED 401 in my react app

Question

Below is my react code snippet. I have verified that the token is correct using postman. Does anyone have ideas what might be missing here ?

export async function getData() {

    const url = buildUri();

    const auth = "Bearer " + await getAccessToken(); // api call to get access token
    console.log("Using auth: ", auth);

    var res = fetch(url, {
       method: 'GET',
       mode: 'no-cors',
       headers: {
           "Content-Type": "application/json",
           "Authorization": auth
       }
   }).then(response => {
       return response.json();
   }).catch((error) => {
       console.log("Error getting data: ", error);
   });
   console.log('got res: ', res);
}