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<@ULVA73B9P> what does this error mean upon flow submission?
```Aborted submission of flow run '069f25f9-4625-73c2-8000-d55e00a9ce2b': Server returned a non-pending state 'CANCELLED'```

:white_check_mark: thought for 95.2 seconds

That message usually means *Prefect asked the API to put the flow run into `PENDING`, but the API refused and returned `CANCELLED` instead*.

So in plain English:

*the flow run was created, but the server decided it should not be submitted for execution.*

The most common reason is a *deployment concurrency limit* with a *cancel* strategy.

Example:
- your deployment allows only `N` concurrent runs
- `N` runs are already active
- a new run is submitted
- instead of queueing it, Prefect cancels the new run
- the client logs:
  ```Aborted submission of flow run '...': Server returned a non-pending state 'CANCELLED'```

*Most likely cause*
- Deployment concurrency is set
- Collision strategy is `CANCEL_NEW`

In that case, hitting the limit causes the server to return a cancelled state like:
- `Deployment concurrency limit reached`

*What to check*
1. Open the flow run in the UI and inspect its state message
2. Check the deployment’s concurrency settings
3. Look for other active runs from the same deployment

If this is the issue, your options are:
- increase the deployment concurrency limit
- change the strategy to *enqueue* instead of cancel
- wait for current runs to finish before submitting more

If you want, I can help you confirm whether this is a deployment concurrency issue and show you exactly where to check in Prefect Cloud/UI or in your deployment config.