Theoretically, this kind of transaction is prohibited. If it happens, you just wait to answer the phone. . .

It's easy to buy and sell by yourself. For example, when you sell for the first time, if the market is very inactive and there has been no transaction, then you hang up a purchase order and make a transaction with the one you just hung up, which constitutes self-buying and self-selling, and then you will probably receive a phone warning from the futures company or the supervision bureau or temporarily prohibit trading by phone.