This error is most likely related to your network connection, so it is recommended to disconnect the network and connect again.

To do that, from your iPad:

1. Go to iPad settings and tap on Wi-Fi.
2. Tap on ℹ️ next to the wifi network name.
3. Tap on Forget This Network.
4. Restart the modem/router.
5. Reconnect to the network then try again.