See If you forgot the answers to your Apple ID security questions https://support.apple.com/en-us/HT201485
Given that you have been told that Apple does not have sufficient information to answer your security questions, note that
Security and your Apple ID https://support.apple.com/en-us/HT201303 says “without proof of your identity via security questions and other carefully selected criteria, Apple Support can't help you reset a password or perform any other actions on your account.”
So, since are unable to answer your security questions satisfactorily, we won't be able to help you with your problem unless you have an extenuating circumstance (e.g., you have the receipt for the purchase of a pertinent device with its serial number on it or you have a court order instructing Apple to assist in the provision of access to a decedent’s information from the deceased person's accounts).
If you think you have an extenuating circumstance, even one not mentioned above, then use the support options below to get help in solving your problem.
If pertinent, see How to request access to a deceased family member's Apple accounts https://support.apple.com/en-us/HT208510).
Get a call from Apple support to help solve your problem using this
link https://getsupport.apple.com/?caller=kbase&PGF=PGF63005&category_id=SC0245&symptom_id=23362
Apple ID Support https://support.apple.com/apple-id
Apple ID account security for country-specific and
region-specific help https://support.apple.com/en-us/HT204169
Get Support: We’re here to help https://getsupport.apple.com/. Go through
the options to find the best support option.
