# 16099: Unexpected conference status

Log Level: ERROR

## Description

This error means the conference is not in the status required for the operation you're trying to perform. A conference can be `init`, `in-progress`, or `completed`, and participant actions only apply to active, in-progress conferences. Use `statusCallback` to track conference and participant state changes instead of polling.

### Possible causes

* You tried to manage a participant after the conference had already ended. The Participant subresource only manages active participants of in-progress conferences, and ended conferences do not return associated participants.
* You tried to act on the conference before it reached `in-progress`. A conference is created when the first participant connects, but it does not start until the second participant joins or a moderator joins, if one is configured.
* You identified the conference by `friendly_name` and matched the wrong instance. Multiple conferences can share the same `friendly_name`, and only one of those conferences can be in-progress at a time.

### Possible solutions

* Wait until the conference is `in-progress` before adding, muting, removing, or inspecting participants. Use `statusCallback` to react to conference and participant changes.
* Use the specific `ConferenceSid` for the conference instance you want to manage. Do not rely on `friendly_name` when more than one conference can exist with the same name.
* If the conference has already ended, capture participant details from `statusCallback` or use the Voice Insights API for post-call participant data.

#### Additional resources

* [Conferences resource](/docs/voice/api/conference-resource)
* [Conferences Participants subresource](/docs/voice/api/conference-participant-resource)