When my Taobao account is logged in, I am required to send a short message to my mobile phone for verification and charge a short message fee. What happened?

This is generally not the case. Taobao login needs SMS verification, because your account has the function of secondary verification and protection. You can go to my Taobao-Account Management-Operation Protection Settings page to cancel, or contact Taobao customer service to verify the information and help cancel. However, receiving SMS is free and there is no charge. If your mobile phone charges, you can keep relevant vouchers and feedback them to Taobao staff for verification.