Email firstname.lastname@example.org. Our agents are generally available 4 am - 11 pm Pacific time, M-F and 8am - 11pm Pacific on Saturday and Sunday. If relevant, please include your zyBook code and/or screenshots of your issue.
We don't have a support phone number, as most issues can be handled efficiently via email.
When you email email@example.com, you should initially receive an auto-reply (typically in under a minute). If you don't receive an auto-reply, then something is amiss. Perhaps our auto-reply got filtered as spam on your end, meaning you likely won't see our actual reply later -- please check your spam folder, and if our message is there, configure your email system so that messages from us are not spam. Or perhaps we did not receive your email, such as if you sent to a wrong address, or maybe your email was filtered as spam by our ticket system (rare but it happens) -- please try resending.
Also, if you are reporting a possible error in our content, it is better to use the feedback button in the content closest to the issue, and select the "Error" box. Doing so also emails firstname.lastname@example.org but includes a direct link to the content with the issue, along with other useful info. You'll receive an auto-reply email as well, as discussed above.