Activation lock on old phone

Activation Lock is an anti-theft device. We cannot remove it and Apple will not under these circumstances. Apple also will not disclose the full Apple ID, as a matter of protecting the owner’s privacy.

if the seller will not, or cannot, assist with removing the Activation Lock, the phone will forever remain a “brick.” A seller who voluntarily parts with an iPhone should prepare it for a new owner as described in

What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support

damien_091 wrote:

i recently bought a iphone 4s from someone for kid, not knowing it was locked. The phone is linked to an apple id, that i have no clue what it is, how do i get find the apple id?

You ask that someone you bought it from, can't remove activation lock without original owners information.