File/design disappeared from Photoshop for iPad

Photoshop Version 5.5.2

iPad Air (5th generation) Version 17.5.1 

I'm afraid I can't offer any clue on how to reproduce this. A couple of weeks ago my partner made a series of fun Halloween pumpkin designs on photoshop for iPad. She spent many hours on them, and when finished, she printed out several sheets of them to use as stickers. This was all in our home, with her iPad connected to wifi. Today, she went looking for that file to make some edits and print some more for students of hers. The file was gone. I spent the last couple of hours combing through all the troubleshooting I could find, and other threads on this forum, and the design is just gone like it never existed. It's not in recently deleted. It's not visible in the cloud from her laptop. It's just gone.

Now she did probably never give it a name or manually export it (aside from when she printed it), so it should have just saved with a default name in the default place for Photoshop on iPad. As far as I can tell, Photoshop on the iPad does not give us an option to automatically save locally to the iPad.

Given that saving on the cloud seems like it might be unreliable, how can we make sure this never happens again?