Apple ID disabled

How can I unlock my iPad air2 when the Apple ID has been disabled.

I was told 6yrs ago that the screen was blown by the apple shop it was out of warranty and was going to cost £280 so I tossed the I pad into a drawer until now, I was about to get rid of it when it turned on and the screen works. I don’t have an iPhone and don’t have the same phone number that is linked to the apple account.

I phoned apple support and provided them with all the details of the account, the serial number of the iPad, when and where I purchased the iPad 8yrs ago, yet they can’t help without proof of purchase.

this iPad is 8yrs old how the **** am I supposed to get proof of purchase to unlock the iPad, I’m not bothered about having the account deleted and the iPad resetting.