I can't synch my mac Digital Editions library to my ipad Digital Editions library

When I download a book on my computer's Digital Editions, I don't see it updating on my ipad Digital Editions. I deathorized on both and also uninstalled the application on both. Then I reinstalled and reauthorized onto the same log in however I do not see the library synchronzing. I was speaking with customer service representative, Sachin, who was so patient with me but we were not able to solve this.

Does anyone else have trouble synching MAC and IPAD together?