Apple ID locked

Hi - see whichever of the following is most appropriate.

Forgotten apple ID Password

https://support.apple.com/en-gb/HT201487

Forgotten apple ID

https://support.apple.com/en-gb/HT201354

Apple ID recovery

https://support.apple.com/en-gb/HT204921

If you think your apple ID has been compromised

https://support.apple.com/en-gb/HT201487

You can only unlock it with the apple ID. If you've purchased the phone used then you will need to take it back to the seller and ask them to unlock it or give you a refund.

If it is locked to your own apple ID, and you've forgotten it, then you will need to recover it using the links I gave above.

If it is the apple ID itself which is locked, then try this link:

https://support.apple.com/en-gb/HT204106