I signed into an old iPad with iOS 9 now I want to reset it and remove my Apple ID but it won’t let me.. it keeps saying verification error… error connecting to the Apple ID server.
[Re-Titled by Moderator]
iPad Pro (3rd generation)
Unfortunately, on devices running an older version of the iOS 9 operating system, the process of resetting and deleting your Apple ID may be more difficult due to changes in security and authentication methods. Sometimes a simple reboot can help solve some problems. Make sure your iPad is connected to Wi-Fi or mobile data and that the connection is stable.
If possible, try updating the operating system on your iPad to a newer version.
Unfortunately, on devices running an older version of the iOS 9 operating system, the process of resetting and deleting your Apple ID may be more difficult due to changes in security and authentication methods. Sometimes a simple reboot can help solve some problems. Make sure your iPad is connected to Wi-Fi or mobile data and that the connection is stable.
If possible, try updating the operating system on your iPad to a newer version.
This may not fix the verification error. but this is Apple recommended procedure to clean you iPad
What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support
Looking forward to your answer
How to fix Verification Error and remove Apple ID on iPadOS 9
