Activation lock my other iphone

Do not remove the device from your Apple ID account. Tha's it.

If you remove the device from your account after you erase it, Activation Lock will be turned off. This allows another person to turn on and use your device.

Activation Lock is designed to keep your device and your information safe in case your iPhone, iPad, iPod touch, Apple Watch, or Mac is ever lost or stolen. If you erase your device without signing out of iCloud first, it might still be protected by Activation Lock. Whether you erased your own device or bought one from someone else, you can turn off Activation Lock by entering the correct Apple ID and password.