It piled up more orders in stead of just closing the damn position.
I've seen something similar to your screenshot too. I blamed it on lag: if clicking the button doesn't instantly work, it's quite normal for a computer user to click a few more times "just to be sure". It turns out all those clicks still get processed later.
You successfully snatched all of my funds.
This wan't a bug this is done on purpose i have seen it many times over the years.
That accusation isn't necessary: OP is paying testers, that makes it obvious they're looking to find and fix problems.
Now we will just have to wait until the first 'Tickspread scammed me' topics pop up all over the net.
You have a good point though: this shouldn't happen when the site goes live, or it will lead to scam accusations.