All possibilities are covered below. This read pertains to activation lock on an iDevice. Note that no one here is authorized to provide instructions for removing activation lock and that activation lock is a theft deterrent system. But you can turn activation lock off under the conditions mentioned below.
See Turn off Activation Lock https://support.apple.com/en-us/HT201441See this heading If you erased your own device It says: "If you don't sign out of iCloud before you put your device in recovery mode and restore, it might remain in Activation Lock. That means you need to enter the same Apple ID and password that … was used when … [the device was last set up].
[Use] forgot your Apple ID or your Apple ID password [to recover the needed credentials if you don't know them.]
If you have iOS 11 or later and your account is protected with two-factor authentication, you can turn off Activation Lock with your device Passcode. Tap Unlock with Passcode, then tap Use Device Passcode."
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Otherwise, the existence of activation lock guarantees that the pertinent security questions cannot be answered satisfactorily. In such cases Security and your Apple ID https://support.apple.com/en-us/HT201303 is relevant.
This document says “without proof of your identity via security questions and othercarefully selected criteria, Apple Support can't help you reset a password or perform any other actions on your account.”
Thus, we can do nothing to help you, except to mention that Apple support might help you if you have an extenuating circumstance (e.g., you have the receipt for your purchase of a pertinent device with its serial
number on it). If you want to contact Apple support to discuss any possible extenuating circumstance, see these support options:
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.
