It may be that there are too many people logging in to official website at the same time, which limits the browsing in official website. Students need to wait patiently. After a period of time, when official website's visits decrease, they will enter official website again. It may also be a computer network problem, check the network or restart the computer; I don't rule out my own computer network problem. In this case, I can choose to shut down and restart, and then try again in official website. At the same time, you should also check whether your network is unblocked. If you can't get online, you can't go to school, official website.