Web Messaging SDK proactive notification 400 Bad Request on closed sessions

Trying to send a proactive notification via the Guest API for a session that was closed yesterday. The call to POST /api/v2/conversations/messaging/sessions/{sessionId}/notifications returns a 400 Bad Request with message ‘Session not found or inactive’. Is there a way to re-open or target the session, or do I need a new ID?

Guest APIs don’t support notifications on closed sessions. You’re hitting a hard limit there. Start a new session if you need to push a message.

The docs say sessions are stateless after closure, so that 400 is expected. You can’t revive them. Just spin up a new session.