1. Network problem: Please check whether your mobile phone network connection is normal, or try to open the QR code on another network.
2. The QR code is damaged: Please check whether the QR code is damaged or smeared. If it is damaged, please regenerate the QR code.
3. QR code recognition software problem: Please confirm whether the QR code recognition software you are using is normal. If it is not normal, please uninstall and reinstall.
4. Mobile phone system problem: Please confirm whether your mobile phone system is updated to the latest version. If not, please update to the latest version and try to open the QR code.
5. WeChat version problem: Please confirm whether the version of WeChat you are using is too high or too low. If yes, please update to the latest version and try to open the QR code.
If the above methods can't solve the problem, it is recommended to contact Yi Campus customer service or technical support for help.