In the Trader Workstation you have the option of deactivating the working order while you modify. Once an order has been transmitted and before being filled, you can right-click on the order line and select “Deactivate” in the drop-down menu. This will deactivate the order while you make modifications.
If you want to modify parameters other than Price or Quantity of an order in the TWS, you must cancel the working order and create and transmit a new order. This practice is commonly required by order destinations.
Once an order parameter is modified, you are required to resubmit the order. The modification will not take effect until the order is resubmitted.