See if anything here helps. If necessary, you can use account recovery as explained in the link at bottom of the article.
Verification code - how to get one and sign in with two-factor authentication. *
If necessary, if you are the original owner, contact Apple. Apple can remove the ID if provided the required paperwork to include the original purchase receipt with the serial number on it.
Request additional support for unlocking your device. -
You used to be able to take the device, the original purchase receipt with the serial number, and a photo ID to the nearest Apple Store (if it has reopened) and have them remove the ID. This may have changed, so call the store before going to make sure they can help.
Genius Bar Reservation and Apple Support Options - Apple. -