91308: Sink endpoint did not respond in time

Twilio records this error when Event Streams establishes a connection and transmits an event to your sink, but the sink fails to return an HTTP response before the timeout limit is reached.

Because Twilio did not get a response from your sink, Twilio will automatically retry event delivery per retry policy. To prevent duplicate processing when retries occur, your sink should treat Event Streams delivery as at-least-once delivery and deduplicate incoming events using the unique Event ID.

• The sink executes time-consuming operations, such as synchronous database writes, complex computations, or downstream API requests, before returning an HTTP response.
• A service downstream from your handler experienced high latency or a timeout.
• High incoming event volume exhausted available server resources.

• Acknowledge incoming payloads immediately with an HTTP 2xx status code, offloading long-running operations to a background queue or worker process.
• Monitor your sink response latencies to identify transient slowdowns under load.
• Ensure your sink is sized appropriately for peak concurrency.

• 91300: Event delivery to sink failed
• 91306: Sink endpoint returned a server error
• 91307: Could not connect to sink endpoint

• Event Streams overview
• Sink resource
• Subscription resource