To find your LCP Passphrase (Reading Key), on the download page, once you have downloaded the ebook, please scroll down and your Reading Key will be displayed.

Otherwise, if you sign in to your account on eBooks.com, then on the desktop website in your account area there will be Reading Key page that displays your Reading Key. On the Mobile website press the menu icon, then press My Account, then press Reading Key (you may need to scroll down the page to find it).

Or if you are already signed in to your account please use this link: https://www.ebooks.com/account/lcp/

If your device is not accepting your reading key, you may need to update the firmware on your e-reader. Please see this help article for more information.