This has happened two times already. I reported it immediately once it occurred. The staff said they are checking. None called back. Also someone working in IB here asked me to submit my account details. I did. Still no response. How could I place my trust and trade if even the most basic function - stop loss - has bugs? I have reported various bugs about orders for the last few months. None of them have been fixed so far. Back to the stop loss problem, here's what happened. I created a buy order of an HK stock with a stop limit attached. The buy order was executed. The price went up and I changed the stop price several time. Finally the stop price was adjusted to .69 (limit price .64). In other words once the price reached .69, a sell order of .64 would be sent to the market. The price dropped to .69. At that time the price was still struggling at between .68 and .69. But my stop loss was just stuck doing nothing. I had to submit a market sell order instead to exit manually. At that time I was exited at a much worse price. Testing in PaperTrader. The stop-loss works. It just doesn't work when it comes to reality.