Touch ID problems
I tried Touch ID on my iPad Air 4 but it came with ‘unable to read this fingerprint, try again’
iPad Air, iPadOS 15
Question marked as
Start here >>> If Touch ID isn't working on your iPhone or iPad - Apple Support
If you continue to experience difficulties, you might be best advised to seek assistance directly from from Apple Support. You can contact the Support Team using the Get Support link at top-right of this page. Alternatively, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:
https://apps.apple.com/gb/app/apple-support/id1130498044
You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to test and assess your iPad: