Unable to download digital books from my library to my KOBO Aura H2O e-reader.

Unable to download digital books from my library to my KOBO Aura H2O e-reader. I am no longer able to download digital books borrowed from my municipal library on my KOBO will have H2O 2nd edition e-reader.  Adobe digital edition does not work on my Mac and it's impossible to download ADE on App Sstore for Mac.