this problem happened with me , and it belongs to iCloud , and I need to used so important , can please anyone help me ??
iPad Air, iOS 10.0.2
Hi. The Passcode on your iPad is the four or six digit code that you have to enter to unlock the device. It has nothing to do with your Apple ID or two-step verification. Are you able to unlock your device? If you are, then please describe the steps that lead up to your problem. Since you changed your Apple ID password, you'll need to go to both Settings > iCloud and Settings > iTunes and app store and logout from your Apple ID, then log back in with the new PW.
thank you Diana for your support , I tried to do what u said but I didn't work, but I took a screen shot of the error but I didn't know how to attach it here
I had a problem with my iPad Air 2 when I changed my Apple ID Password , the problem is it shows me a Massage says ENTER PASSCODE , and then it says your PASSCODE will be used when signing in with new device , but when I but the code it shows me Fail
