Error while trying to revoke token

Hi,

I have been able to successfully login using my app's client secret & id but I can't revoke users' auth token as I keep on getting CORS related error

const data = `client_id=${clientId}&client_secret=${clientSecret}&token=${refresh_token}`

axios
 .post('https://api.box.com/oauth2/revoke', data, {
 headers: {
 'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8'
 }
 })
 .then(() => {
 console.log('Logout success')
 dispatch({ type: USER_LOGOUT })
 })
 .catch(error => console.error(error))

window.fetch(`https://api.box.com/oauth2/revoke`, {
 method: 'POST',
 body: data,
 headers: {
 'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8'
 }
}).then(() => {
 console.log('Logout success')
 dispatch({type: USER_LOGOUT})
}).catch(error => console.error(error))

I made the post request using both fetch and axis but I get the same error. Any ideas on what's going wrong here?

Appreciate all the help!

EDIT: I am using oAuth2 for user authentication