Why does it close the order by itself, I don't understand this part much, many people often get it wrong

At midnight, I saw an email notifying me to close the order. I thought I had 10u and my account would be burned to 200u. I hurried in to check and it turned out that Brother Bằng was just messing around 😂😂😂 thank you, bro, I don’t have any TP either.