What’s your App ID?
32616411
What endpoint are you using?
POST /2/webhooks
What API version are you on?
2
Are you using a library or SDK? Which one?
No library, direct HTTP requests from a native Swift macOS app
What is the issue?
503 Service Unavailable on every attempt to register a webhook via POST /2/webhooks
Steps to reproduce the issue
Step 1: Generate App-Only Bearer Token via POST /oauth2/token (succeeds)
Step 2: POST /2/webhooks with Bearer token and a valid ngrok HTTPS URL
Step 3: Receive 503 every time
What is the error message?
{“title”:“Service Unavailable”,“detail”:“Service Unavailable”,“type”:“about:blank”,“status”:503}
When did it start?
March 20, 2026. First time using this endpoint.
What have you tried to troubleshoot?
-
Confirmed Bearer token is valid (generation returns 200)
-
Confirmed webhook URL is publicly accessible via ngrok
-
Tried multiple times with consistent 503 results