Digital Editions won't let me read a library book on Samsung Android tablet

      Just borrowed an ebook from a library.

      Adobe Digital Editions on my desktop lets me open and read it.  However, I want to read it on my Samsung Galaxy Tab A (2017) tablet.  So I downloaded ADE to the tablet, but ADE won't let me open/read it. 

     It wants me to authorize with a vendor, but my library is not on the drop down vendor list.  

     (Overdrive.com is on the vendor list.  I access Overdrive.com through the library.  But ADE won't recognize the library's logon/password.  So I created an Overdrive.com account based on my email address.  But it won't open the book because it isn't from Overdrive.com.  The book was not borrowed through Overdrive.com; from the library itself.)

     I was able to 'authorize' ADE on my desktop (several years ago) without choosing a vendor, but I don't see that option on the tablet.

      Any help?