Hello, I am trying to integrate an external PHP script hosted on Hostinger to register users automatically via the Invision Rest API. However, my API requests are being blocked with an "INVALID_ACCESS_TOKEN" error. I believe Cloudflare is blocking the request, and I do not have control over it. Is there a way to whitelist my Hostinger server IP or provide a way to bypass Cloudflare's WAF for API calls?

We cannot whitelist servers unfortunately. However if you are getting that error, you are not being blocked, as thats the response you would get from the API if indeed you are passing the wrong access token

I've hidden your screenshots as they show URLs and API keys.

As you can see here, the error you're getting is when using the OAuth API that you are not sending the correct token: https://invisioncommunity.com/developers/rest-api

As custom code is outside our scope of support, you would need to verify how you're accessing your API and if you are intending to use the OAuth API. If you're using the REST API, then Basic Auth would be required there with the API Key.