Something has stalled - possibly due to your WiFi or internet connection being interrupted.
If the problem hasn't cleared, connect your iPad to its Power Adapter, allowing the iPad to charge. While connected to the Power Adapter, perform a forced-restart:
Force restart iPad (models with Face ID or with Touch ID in the top button)
If your iPad doesn’t have the Home button, do the following:
- Press and quickly release the volume button nearest to the top button.
- Press and quickly release the volume button farthest from the top button.
- Press and hold the top button.
- When the Apple logo appears, release the top button.

Force restart iPad (models with the Home button)
Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

After restart, keep the iPad connected to its Power Adapter during the setup process - as this will keep the WiFi connection active.