Sorry to hear of your continued dilemma.
I “suspect” that you’ll need to register for Apple’s Two Factor Authentication. (2FA)
It’s alluded-to in the article at the link already provided.
2FA is Apple’s current, MUCH improved — less phishable — security system which does away w/ “Security Questions” entirely.
Read and FULLY digest the below linked articles BEFORE activating 2FA.
Pay particular attention to the sections on “Trusted Numbers”
Your iPhone should NOT be a Trusted Number. (as it’s already a Trusted Device)
You’ll NEED these additional Trusted Numbers if (when) you loose access to your Trusted Devices.
Don’t hesitate to post back if you have any questions.
Two-factor authentication for Apple ID - Apple Support
Get a verification code and sign in with two-factor authentication - Apple Support