You probably haven't been flat. Need to check your trades summary page to be sure. And check your executions page to be see what executed. I was long 2, had a sell in, 1 sold, I watched for the other to sell, it didn't, the order disappeared off the screen as if both out sold, and the 1 remaining disappeared from the position column showing I had none. I checked the executions page, and it only showed 1 sold. The summary page showed I was still long 1. Fortuately I got an extra point out of it. :-)
Another possiblitiy. Do you cancell any orders? Could be a bug where when you cancell it disappears off the screen, but still is enforce. Then when the price gets to it, it goes through. But your trade execution and summary pages tell what has actually happened, and what you have.
I missed tech support. I'll call them tomorrow and explain it to them.
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