Hi agent-land,

"How to close it?"
Closing an app on iPad
https://support.apple.com/en-us/HT212063

I'm not clear about what you experienced. With no input on your side, it has motion (revolving) on the screen?
This behavior continues after restarting even, meaning it is reproduce-able.

Would you mind:
Explain it a little bit more in detail
OR
check with the tech support
https://www.maxon.net/en/support-center

I hope that helped in one way or another; if not, please share more information. I'm happy to look into it!

Cheers