I checked the records for your email address.
It looks like on 2013-09-03 we received a complaint from your email provider of spam to your email account. This can happen if an email is marked as spam or blocked. If you have another person sharing your email account, you may want to let them know you are expecting emails from us.
From then on, it looks like we have had 6 additional failures to deliver your email that caused your email address to be unsubscribed from our list each time.
I will add you the email list again, but you may want to take these additional steps:
1. Add firstname.lastname@example.org
to your address book.
2. Make sure your inbox is not full and you have plenty of room to receive emails. (You may need to login to your webmail and check)
3. Make sure NOT to mark emails from email@example.com
as spam. It can cause additional failed deliveries.