---
title: 2023: Operation requires a group chat | API Docs
description: The request uses a group-only feature, such as an @mention, in a direct message chat.
---

The request uses a feature that is only supported in group chats. This is an HTTP 409 error returned by the message send endpoints (`POST /v3/messages`, `POST /v3/chats`, `POST /v3/chats/{chatId}/messages`) when a text part includes a `mention` and the target conversation is a direct (1:1) chat — including a send to a single recipient, which creates a direct chat.

@mentions address a specific participant of a group conversation, so they are rejected rather than silently dropped when the chat has only one other participant.

## Troubleshooting

- Remove the `mention` field from text parts when messaging a direct chat
- To @mention someone, send the message to a group chat that includes them — the mention target must be one of the chat’s participants
- Check the target chat with `GET /v3/chats/{chatId}`: mentions require `group: true`