Why does the verification code bound to my mobile phone always expire?

As more and more users use Sina's various services, at the peak of login, sometimes the login is slow and unstable or the verification code is incorrect, or some unpredictable problems appear. You can try refreshing the page, or log in later and try again. Or check from the following aspects: 1. If you enter the correct user name, password and verification code, you will return to the previous login page after logging in without any error prompts. This is usually because you have disabled cookies in your browser. You just need to click on the tools in the browser to enter the Internet option, set the security level to medium in the security settings or enable cookies directly at the custom level. (IE6.0 users have adjusted the privacy level in Internet options to medium) 2. If the page can't be displayed, the verification code is wrong or the server can't be found when logging in, it's because your server is being maintained or there are too many users visiting at the same time. In this case, you just need to wait patiently and try again later.