---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/45203#article
headline: "45203: Requested Chat User not found"
url: https://www.twilio.com/docs/api/errors/45203
inLanguage: en
dateModified: 2026-06-09T11:00:42.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 45203: Requested Chat User not found

Log Type: APPLICATION

Log Level: ERROR

## Description

Twilio could not find the Chat User requested for a Chat Channel operation. This error usually means the Chat User was deleted, was never created, or the request referenced the wrong user identity.

### Possible causes

* The Chat User for the agent or end user does not exist.
* The request uses an incorrect Chat User identity or SID.
* A custom implementation deleted the Chat User that Flex expects to use.
* User provisioning or identity synchronization did not complete as expected.
* An agent signed in with identity data that does not match the existing Chat User record.

### Possible solutions

* Verify that the Chat User exists for the identity used in the request.
* Confirm that your implementation passes the correct user identity and any related Chat Channel identifiers.
* If you manage Chat Users outside of Flex, make sure your application does not remove users that active or future conversations depend on.
* Retry after confirming that user provisioning completed successfully.
* If you use single sign-on, verify that the user profile information synchronized from your identity provider is correct and consistent.
* Have the agent sign in again if the user record may not have been created or synchronized correctly.
* Review any custom Flex or backend logic that creates, updates, or deletes Chat Users.

#### Additional resources

* [Flex documentation](/docs/flex)
* [Programmable Chat documentation](/docs/chat)
* [Set up single sign-on for Flex](/docs/flex/admin-guide/setup/sso-configuration)