You can only cancel an order if it hasn’t been filled yet. To cancel a pending order:
From the Overview page of the stock you placed the order for, tap on the order listed under Upcoming Activity.
On the order details page, tap Cancel Order.
Once you submit the cancellation, the order status should change from Accepted to Canceled.
Important Information About Order Cancellations
While you can cancel unfilled orders, there is a small risk that your cancellation request may not prevent the order from being executed.
Here’s why:
There is a slight delay when sending a cancellation request to the exchange.
During that delay, your order could still be filled before the cancellation is processed.
The longer you have the order screen open before tapping Cancel, the higher the risk that the order status shown to you is outdated — the system does not update the order status live while you're viewing the screen.
Tip: If you need to cancel an order, act quickly to minimize the chance of it being filled before your cancellation request reaches the exchange.