Static S3 site AJAX to API Gateway "not allowed by Access-Control-Allow-Origin" despite wildcard header [closed]

I have:

• Created a static website in AWS S3
• Created an API Gateway resource that calls Lambda
• Enabled CORS on the API Gateway
• Verified the propery CORS response using Postman (returning Access-Control-Allow-Origin: *)
• Made an AJAX request to the endpoint using axios.post(...)

Yet, we get the following error:

Failed to load resource: Origin http://mys3site.com is not allowed by Access-Control-Allow-Origin.

This is mind boggling to me because I have clearly enabled a wildcard Access-Control-Allow-Origin.

Edit

The question was closed because "debugging details are needed". I'm not sure what that means given that this configuration is done through the AWS console rather than through code, but here is my axios post request:

axios.get(ENDPOINT.server)  .then((response) => {      this.update(response.state);  })  .catch((err) => {      this.error(err);  });  

Here are the headers returned by OPTIONS to the same endpoint;

Date: Fri, 26 Mar 2021 01:02:26 GMT  Content-Type: application/json  Content-Length: 0  Connection: keep-alive  x-amzn-RequestId: xxx  Access-Control-Allow-Origin: *  Access-Control-Allow-Headers: Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token  x-amz-apigw-id: xxx  Access-Control-Allow-Methods: DELETE,GET,OPTIONS,POST  

https://stackoverflow.com/questions/66808890/static-s3-site-ajax-to-api-gateway-not-allowed-by-access-control-allow-origin March 26, 2021 at 07:18AM