Dear, the problem has been solved.

Someone called me to deal with my problem, but he did nothing. Now I can't reach him and the customer service keeps delaying.

I contacted the customer service who let me wait constantly instead of providing any solution.

I set the stop loss point, but did not close the position at my stop loss point. Straightly manipulated my stop loss point and passed 3 pips to liquidate the position, which resulted in a loss of more than 48,000 US dollars for my 150 lots order.