Sorry to cause trouble to the teacher, please ask the teacher: "I directly used the teacher's courseware code to test, but when I opened the login page for the first time every day, I successfully logged in and entered the page normally, but when I used logout() (or directly After visiting the page to log in, it prompts "Not logged in, please log in first"), use the login method again (without modifying any content), click the OK login button, but there is no response, and the username and password database cannot be read (enter the account password casually) No response), teacher, what is causing this? Restarting the PHP toolbox, deleting the cache, and changing the browser to log in have no effect