Folder full of sub folders full of PDFs shows as empty on main iPad WD app

I have uploaded a folder onto the public part of my MyCloud, which is full of sub folders which are full of PDFs. I can see this on my mac, and on my iPad through the WD photo app, but the folder shows as empty on main iPad WD app. One of the main reasons for getting MyCloud was to be able to access these PDFs remotely using iPad … Please help!

Are you using the WD Photo app or the WD My Cloud app on your iPad?

I’m using both! The point is I can see the sub folders and content (though obviously can’t open PDFs) through the WDPhoto app, but can’t see anything through the main WD MyCloud app