What should I do if qq is in protected mode and I forget the security? Moreover, the appeal has been unsuccessful and there are systematic errors.

First of all, the reason why QQ enters protected mode is that Trojan virus exists in your computer, which threatens your QQ security. So I suggest you use Tencent Computer Manager's antivirus function to disinfect your computer first. After antivirus, you can complain your QQ number to QQ Security Center. After the appeal is successful, the protection mode can be released and used normally. If the protection mode of QQ cannot be released through appeal, you can contact the customer service of QQ Security Center to help you. You can download the latest version of Tencent Computer Manager here:

Tencent Computer Manager Enterprise Platform: /c/ Manager/