"Can't Open Presentation" error in Keynote on iPad Pro

This is the error message I receive when I open Keynote to create a presentation.

I’ve read previous posts reporting similar error messages, so I rebooted the iPad Pro, and the issue remains.

The iPad is current on updates and the wifi reception is strong.

IPadPro

iPadOS

Currently running 16

Updates in progress: 17.4.1

[Re-Titled by Moderator]