Why is my mobile phone number bound to my vivo account security phone, but I don't have the SMS sending function?

The mobile phone number/emergency contact/email address/password protection bound to this account is still in use. You can go to mobile phone settings-click top account-security and password-secure mobile phone number-modify secure mobile phone number, and reset the mobile phone number according to the prompts. If the system detects that the account is highly secure, you can directly set a new secure mobile phone number. If you are prompted for authentication, you can modify it after authentication.