# campaign_operation_in_progress

- HTTP status: 409
- Retry: After Retry-After
- Execution: not started
- Admin needed: no

**Another start or resume is in progress.** Only one start or resume runs per campaign at a time. Another request holds the campaign right now.

## What it means

The API returns HTTP 409 with `error.code` set to `campaign_operation_in_progress`. The default message is: "This campaign is being started or resumed by another request. Retry shortly."

## Common causes

- Two clients started or resumed the same campaign at the same moment.

## How to identify it

Check the response status (`409`) and `error.code` (`campaign_operation_in_progress`). Branch on `error.code`, not on the message text: messages can be reworded, codes do not change within v1. Log `error.request_id` (also sent as the `X-Request-Id` header) so support can find the request.

## How to fix it

- Wait `Retry-After` seconds, retrieve the campaign, and act on its new status.

## Retry guidance

Wait for the number of seconds in the `Retry-After` response header, then retry.

## Did anything happen?

This request was refused before any call was placed and before anything was charged.

## Idempotency

Nothing was done by this request. Retry after the wait (with the same key if you sent one).

## Who can fix it

The developer who sends the request can fix it; no administrator action is normally needed.

## When to contact support

If the error persists after the steps above, contact [support@relationsai.com](mailto:support@relationsai.com). See [Support](/resources/support) for what to include (the `request_id`, the time in UTC, the operation, and whether you used a test or live key) and what never to send (API keys, Authorization headers, webhook signing secrets, recording links, transcripts or customer data).

## Example error response

```json
{
  "error": {
    "code": "campaign_operation_in_progress",
    "message": "This campaign is being started or resumed by another request. Retry shortly.",
    "details": {},
    "request_id": "req_rg4otkxbmsqp5uhol6deftiv",
    "retry": "after",
    "doc_url": "https://docs.relationsai.com/errors/campaign_operation_in_progress"
  }
}
```

## Operations that can return this error

- [`POST /campaigns/{campaign_id}/start`](/api/campaigns#start-a-campaign): Start a campaign
- [`POST /campaigns/{campaign_id}/resume`](/api/campaigns#resume-a-campaign): Resume a campaign

See all codes in the [error-code reference](/fundamentals/error-codes).