When you access the CK-12 app in Canvas, Canvas will pass to us the email address you used to log into Canvas. We will then create an account for you if needed, or log you into our system if an account already exists with that address.
For example, you may have created content or put items in your library while logged into CK-12 with the email address email@example.com. If you then log into Canvas with the email address firstname.lastname@example.org, you'll be logged into *that* account when you access the CK-12 app in Canvas, *not* the email@example.com account. So, your CK-12 library and other items won't match.
You would either need to log into Canvas with the same email address that you used on your CK-12 account, or you'll need to change the email address on your CK-12 account to match your Canvas account.
To change the email address on your CK-12 account, just follow these steps:
1) Click your name in the upper right corner of the site.
2) Click Settings.
3) Change your email address.