---
title: 2036: Outside customer window. | API Docs
description: The chat's customer service window is closed.
---

**HTTP status:** `422`. May also be reported as a field-level finding in `error.details[]`.

Only an approved template part may be sent when the customer’s 24-hour window has lapsed or never opened. Nothing was sent.

## Troubleshooting

- Read error.context.expires\_at: a timestamp means the window lapsed, null means the customer has never messaged this number.
- Send a template part, or wait for the customer to reply, which reopens the window.

## Related

- [Sending messages guide](/channel/whatsapp/guides/messaging/sending-messages/index.md)
- [Templates guide](/channel/whatsapp/guides/templates/index.md)