Today, my phone version of Diarium reverted back to the Free App (2d time in past 60 days). I have had the PRO version for three years. Thankfully, I also have the desktop version, which I then baked up. Then, I deleted the phone app, and reinstalled the app, and waited for my 2600 attachments and thousands of entries to come back to the phone and all seems ok now. I just had to re-type four entries from today into my desktop app before backing up. I did not do anything new or different that I am aware of. In fact, I think it occurred while I was voice typing a journal entry because I noticed the font changed back to the default free font.
I have a Samsung S20 phone
ONE UI 5.1
Android Version 13
Diarium Version 3.0.5.0 (NOW, as of today, when I reinstalled it) I am not sure what version before today