It's no use what you do now. I've been in your situation. I suggest you wait until tomorrow, when the external market opens. The main reason is that the relevant futures companies will shut down the relevant servers for system maintenance or system testing, which leads to the above situation.

Answer to the supplementary question: When you confirm that there is nothing wrong with your network, clicking the software "Online" will pop up this prompt for a while, indicating that the server of the related software is closed, so this situation is not necessarily caused by the failure of your network.