# 104007: Session channel not ready

Identifier: `session_channel_not_ready`



An AI Transport send was attempted while the session's channel was not in a usable state, neither attached nor attaching, so there was no reliable channel to publish on.

## What you should do

Retry the send with backoff; the SDK does not queue or retry it for you. It will go through once the channel is attached or attaching again, which usually happens on its own.

## Why it happens

A send requires the [channel](https://ably.com/docs/channels/states.md) to be attached or attaching. The write guard first waits for `connect()` to complete, so by the time a send runs the channel has already attached at least once; this error means it has since dropped to another state, such as detached, suspended, or failed, typically because the underlying connection was lost.

## What you'll see

The error is reported with code 104007 and status 400. The message names the current state, in the form `unable to send; channel is detached`.