You can check your books in your Leanpub library, to see if you've bought a book twice:

https://leanpub.com/user_dashboard/library

If you need to reset your password to sign in, you can do that here:

https://leanpub.com/password_reset

We make it easy to get a refund for any book, within 60 days of purchase. Here are the instructions:

http://help.leanpub.com/reader-help/how-do-i-get-a-refund
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