How can I recover lost data?

I downloaded a book from the internet, which was only available for a short time and imported it into Moon Reader and after an update from Moon Reader the book is no longer there. I can't find it in the file manager. But somewhere it must have been lost and still be there. How does it work? I have to stress that all this happened on the tablet, because I no longer have a computer or laptop.

If your tablet is running Windows, download Recuva_portable and try to get targeted deleted files on your Ebook Reader and then restore your e-book to your tablet. Then you copy that back to the reader.

https://www.ccleaner.com/...le-version

https://diskdigger.org/android

But if it is like on the PC, it may be that your book will be overwritten or already became, if you store / download / install something else. But you can try it. It would be better to start the program externally from a computer without making any changes to the tablet.

https://www.chip.de/...ery-Tools/

I do not have a PC anymore. I found it superfluous, since I only do everything about the tablet anyway, so I sold it

I do not know Windows. I always open Chrome. But can test it despite times

Chrome is the browser. Windows or AppleOS or Android are the operating systems

Thank you very much for the award.