Access to /continue from origin 'http://localhost:3000' has been blocked by CORS policy?


I’m trying to redirect new users to a custom consent page in order to get user consent after the first log using auth0 redirect rules.
The application doesn’t support signup so I had to do this after the initial login.

I followed option 4 from this document
[](https://GDPR: Track Consent with Custom UI)

Added the redirect rule + made a consent page with submit checkbox to save user consent and redirect to the application but I get:

Access to fetch at '' from origin 'http://localhost:3000' has been blocked by CORS policy:
Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

I checked the application CORS, web origin, callback URLs, and all of them are set correctly.

Here is a snippet of the react code that I use on form submit.

const handleSubmit = (event) => {
    let url = window.location.href;
    let params = queryString.parse(url);
      "https://" +
        config.REACT_APP_AUTH0_DOMAIN +
        "/continue?state=" +
        method: "GET",
        crossDomain: true,
        headers: {
          "Cache-Control": "no-cache",
          "Content-Type": "text/html",

Any help appreciated.