I cannot load my e-books bought by Google Play on my Kobo Clara Reader

Hello ! Can someone give me help ?

I have recently got a Kobo Clara Reader. Previously I bought some e-books on Google Play Books. Now I would like to transfer those e-books to my Kobo Reader. I was in contact with a Technician from Google Play today who told me that Adobe Digital Editions may be the problem. I have a different e-mail address for Google and for Kobo and Adobe Digital Editions. Right now I wanted to change my ADE Address and it doesn't work. Finally I have got a lot of troubles with Adobe by changing my address and after more than 1 hour chat nobody was able to help me !