I placed a trigger order that was held at the exchange, which they did not execute on a timely basis. It was a stop loss market order that took 8 seconds to go through, and by that time the other part of my order, which was supposed to get cancelled, already went through. My broker offered to credit the commissions, but said this risk is on me. Does that make sense? Isnt the exchange at fault? Isn't my broker required to take up this issue with the exchange?