ACM file won't open in iPadOS 13.6

[brucek69262238]

The file (an advance copy of a book) appears in the library but it won't open. The same file does open fine on my Mac and with a digital reader, but the app. There are no error messages. I deleted the app and reinstalled it but no luck. The app and OS are both the latest versions and the account is authorized. Does anyone have any suggestions?

[tobinangela63@gmail.com]

I have somewhat the same problem. I downloaded Adobe Digital Editions 4.5 and an e-book, but the book will not open on my PC. When I try to open it, a window appears saying it has encountered an error. Any ideas, please? I am really looking forward to this book!