Pending Order Canceled could happen either when the Master has placed a pending order that has been canceled before triggered. When the pending order has been triggered on the Master but not on the Slave, and when the Master closes the trade, it cancels the pending order on the Slave. The Pending Order Rejected or Pending Order Cancel Rejected happens when the order sent is rejected for any reason by the broker. In all the above cases, if the behavior is not as expected, you are prompted to try again to place an order or to manage the position manually.