If you see that an open order has been deleted without your consent or action, there may be several reasons for this.
Firstly, it is good to know that there is a limit to how long an order can remain open. When an order reaches its expiration, it's automatically cancelled by the exchange. For example, Day orders that are not filled during the trading day are automatically cancelled after the close of the exchange on which the order was placed. For GTC (Good-'Till-Canceled) orders, the maximum time the order can remain active depends on the exchange. To find out how long your order can remain open, check with the exchange where you've placed your order.
However, there are several scenarios where an open order can be cancelled before it expires. The most common of these scenarios are typically related to an event at the exchange where the order was placed, for example, a temporary disruption or other technical issue. In those cases, we aim to inform you to the best of our capabilities.
Please note
There may be other possible causes of cancellation that do not fall within this general categorization (e.g. orders expired due to aging, or corporate actions such as a stock split, merger, or dividend), where we do not notify you. It is therefore wise to monitor your open orders closely.