cannot remember my icloud.com ID
Hi
I have passed my iPad Air to my son, who is trying to complete a restore. He is having an activation problem in that I cannot remember the iClooud.com ID that is required to login to the iPad.
Apple have requested proof of purchase, which is not available, other than a credit card statement showing a purchase was made and a value, but nothing more specific.
Any help gratefully received
iPad Air, iOS 9.2