unlock the old iPhone from ATT

klp_at_home wrote:

Do I still need to unlock?

What do you mean by "unlock"? Do you mean that the phone is carrier-locked to AT&T and you want to unlock it so that it can be used on any carrier? Or do you mean it's activation locked to your Apple ID?

If you are asking about the carrier lock, only AT&T can remove that. If you're just trading in the phone, you don't need to worry about it. If you're planning on selling the phone, it may be important. Contact AT&T.

If you're asking if you should remove the activation lock, unless you plan on continuing to use it yourself, you should remove that.

See here:

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

If you deleted all apps, data, etc you were asked if you wanted to keep the carrier settings in place or delete them before you tapped on "Erase".

Do you recall which option you chose?

If you were & are still using ATT then you should not need to remove ‘carrier restrictions’ (assuming that is what you are referring to).

You can contact ATT if you are seeking to remove any ‘carrier restrictions’

If this is not re: carrier restrictions I am not sure what ‘unlock’ you are referring to.