Not receiving Sign in with Apple Server-to-Server Notifications despite correct configuration

I received a notification stating that we need to register a server-to-server notification endpoint to handle the following three events:

• Changes in email forwarding preferences.
• Account deletions in your app.
• Permanent Apple Account deletions.

However, even though we have registered the API endpoint under our Identifier configuration, it appears that we are not receiving any API calls when these events trigger.

I honestly have no idea what’s going wrong. I’ve checked our WAF logs and there’s no trace of any incoming traffic at all. Is it possible that Apple hasn't started sending these notifications yet, or is there something I might be missing? I’m stuck and don’t know how to resolve this. I would really appreciate any help or insights you could share. Thank you.