Fix duplicates showing up in Moon reader recent list?

[archz2]

I've relied on Moonreader Pro on my Android for a while now as my primary book-reading app.

My folder structure has been a folder titled 'ebooks' in my internal storage of my phone that has no memory card. In that ebooks folder, there are multiple sub-folders for categories like sports, biographies, design, etc. which contain the respective books belonging to the subject.

Moonreader always used to create its own copy in a separate attachments folder.

Whenever I used to click on any book inside any subfolder in 'ebooks' , it used to show in the recent list in moonreader. Now since few days, for some ebooks it is showing only one copy in the recents list, but for other books it is showing duplicate files in the recent list.

The books in the attachments folder have their highlights preserved (which I think has always been the case) while the ones in the 'ebooks' folder don't . I checked whether it could be because of different filenames of the duplicate copies but the filenames are matching exactly.

I think for all this time, Moonreader used to directly open the 'attachment' copy whenever I used to choose the ones in 'ebooks' folder. But all of a sudden, that setting has got changed. What should I do to avoid duplicates showing up in the recents list?