First, let’s attempt resolving this issue with your Apple device by trying a hard reset, then proceed from there if that does not resolve the problem:
Disconnect the device from it's cord, if plugged in.
iPhone 7: press and hold the power button and the volume down button simultaneously for about 10 seconds, or until you see an Apple logo.
iPhone 6S and older, iPad, or iPod touch: Press and hold your Sleep/Wake button (on the top right) and Home button (on the front) simultaneously for about 10 seconds, or until you see an Apple logo.
When the Apple logo appears, release both buttons.
The next thing you should see after the Apple logo is the home screen a few minutes later.
If you do NOT see the Home screen and it is still asking you you supply your Apple ID and password ***** you should do so. It appears the software must have crashed on the iPad.
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Thanks and good luck,