Modify Order

### Modify the parameters of a working order. **Available to:** All authenticated users **Environments:** Demo, Live **[Rate Limit](/api/authentication#request-rate-limits-and-time-penalties):** 750 requests per hour, 1-second back-off, counts all requests Requests changes to a working order — for example, the trigger `price` of a `Stop` or `Limit` order, or the `orderQty`. Identify the order by its `orderId`. A successful request isn't a guarantee that the change is applied: market, exchange, and logical rules still apply, and the order may already have filled or been cancelled. When the request is rejected, the response carries a `failureReason` and `failureText`. **Common Failure Scenarios** - The order already filled or was cancelled, so it can no longer be modified (`TooLate`). - Another command for the order is still being processed (`AnotherCommandPending`). - The new price is invalid for the order type (`InvalidPrice`). **Error Messages** | `failureReason` | Trigger | |-----------------|---------| | `TooLate` | The order already filled or was cancelled. | | `AnotherCommandPending` | A previous command for this order hasn't completed. | | `InvalidPrice` | The requested price is invalid for the order type. | See the `failureReason` enum in the response schema for the complete list of values.