can't into ipad after format

Try:

- iOS: Not responding or does not turn on

- Also try DFU mode after try recovery mode

How to put iPod touch / iPhone into DFU mode « Karthik's scribblings

- If not successful and you can't fully turn the iOS device fully off, let the battery fully drain. After charging for an least an hour try the above again.

- Try another cable

- Try on another computer

- If still not successful that usually indicates a hardware problem and an appointment at the Genius Bar of an Apple store is in order.

Apple Retail Store - Genius Bar

Did you try restarting or force restarting your iPad? Did you try recovery mode?

Try restarting first.

Restart your iPhone, iPad, or iPod touch - Apple Support

IF the Apple Logo is still the only thing that you see on the screen, try using recovery mode and restore again.

If you can't update or restore your iPhone, iPad, or iPod touch - Apple Support