# OANDA order cancel reason: TRAILING_STOP_LOSS_ON_FILL_CLIENT_ORDER_ID_ALREADY_EXISTS

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This is the markdown version of https://openbrokerapi.com/errors/oanda/tsl-on-fill-cl-order-id-exists, written from the same records as that page.

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The error, as text you can copy:

```
TRAILING_STOP_LOSS_ON_FILL_CLIENT_ORDER_ID_ALREADY_EXISTS
```

- Kind: Order cancel reason
- Where you meet it: In the cancellation the API reports, not in the HTTP status
- API: [OANDA](https://openbrokerapi.com/brokers/oanda)
- Status: verified. Source: [developer.oanda.com](https://developer.oanda.com/rest-live-v20/transaction-df/), checked 2026-10-09.

## What does TRAILING_STOP_LOSS_ON_FILL_CLIENT_ORDER_ID_ALREADY_EXISTS mean on the OANDA API?

Filling the order would have created a trailing stop loss order with a client order ID that is already in use. OANDA lists this value as an order cancel reason: it appears in the reason field of an order cancel transaction.

## How do I fix TRAILING_STOP_LOSS_ON_FILL_CLIENT_ORDER_ID_ALREADY_EXISTS?

Use an identifier that is not already in use.

## More on the OANDA API

- [All OANDA API error codes](https://openbrokerapi.com/errors/oanda)
- [OANDA API quickstart](https://openbrokerapi.com/brokers/oanda/quickstart): From credentials to a first call on a demo account, step by step.
- [OANDA API error codes](https://openbrokerapi.com/errors/oanda): 242 decoded, each with what it means, and the fix where the source gives one.
- [OANDA API endpoints](https://openbrokerapi.com/brokers/oanda/endpoints): 33 documented, each with its method, path, parameters and source.
- [OANDA API page](https://openbrokerapi.com/brokers/oanda): The full record: access, authentication, limits and the source for each.
- [Get your OANDA trade history into a spreadsheet](https://openbrokerapi.com/guides/oanda-trade-history): Guide

## Licence and how to cite

The records behind this page are all rights reserved. This file is the page itself, at its own address, in another format. It is not part of the CC BY 4.0 downloads listed at https://openbrokerapi.com/data. Quote from it with a link to the page.

Cite as: OANDA order cancel reason: TRAILING_STOP_LOSS_ON_FILL_CLIENT_ORDER_ID_ALREADY_EXISTS. Broker API Hub, https://openbrokerapi.com/errors/oanda/tsl-on-fill-cl-order-id-exists, newest check 2026-10-09.

Where you rely on a single figure, cite the source and the checked date printed beside it as well. Where this page and a broker's own documentation differ, the documentation wins.