HI @TommyNg1 ,
If you are testing this in production then, your webhook needs to:
- Be accessible from the internet (not using localhost)
- Be reachable over HTTPS
- Correctly respond to a "challenge" request
You can also test it by using challenge request when creating an event registration using a webhook, Adobe I/O Events will first try to verify that the URL is valid. To do this, it sends an HTTP GET request, with a challenge query parameter. The webhook should respond with a body containing the value of the challenge query parameter.
You can follow below link for more details on it:
https://developer.adobe.com/events/docs/guides/
-Tarun