”Samsung account already exists in account manager”.
I had the same problem. The fix is pretty simple for Android Marshmallow 6.0? Just do the following:
Go to Settings 》Applications 》
Application Manager 》 Select Kindle 》
Now here you will find “Permissions” click on that. 》 Grant all 3 permissions I.e Contact, Storage and Telephone .
Now go to your Kindle by Samsung and click Samsung Book Deals and Voila!
Originally published at The Scotto Grotto (org). You can comment here or there.