The Apple ID created with secondary authentication account in which three answers for respective questions , date of birth , rescue mail address should be signed in the iPhone .
If Apple ID is not signed in the device only revealing credit card details if added in the account can help apple support senior care advisors Contact Apple for support and service - Apple Support to identify and verify the account .
Before contacting them the Apple ID address and serial number of the device Mac / iPad / iPhone is essential , apple support doesn't know your Apple ID as users have full rights to change it .
If the these credentials are not known your account can never be opened as if it was created long back .