Factory resetting iPad Air 2

the activation lock is not really on the ipad it's a

theft protection measure on apples servers

it needs to be removed

How to remove Activation Lock - Apple Support

if you don't know your appleID

Recover Your Apple ID - Apple

if that does not help you then you need the assistance

of apple

Additional Support - Activation Lock (apple.com) and or

Get Support (apple.com) , Genius Bar Reservation and Apple Support Options - Apple

Here are the Apple support pages that outline the Activation Lock - and the only mechanisms by which it can be turned off:

Activation Lock for iPhone, iPad, and iPod touch - Apple Support

Turn off Activation Lock – Apple Support

As you will discover, unless you are the owner of the AppleID that was last used to activate the device, you’ll not be able to defeat or bypass the Activation Lock. With documentary evidence that you are the original owner (such as sales receipt showing the serial number), Apple may be prepared to assist - otherwise they and nobody here will be able to help you.

If you have the necessary documentation, Apple have recently introduced a new portal though which you may be able to request release of an Activation Lock:

How to remove Activation Lock - Apple Support & start an Activation Lock support request.

As described, your AppleID account is not accessible; you are going to need the assistance of Apple Support to resolve your issue.