Make sure article emails ("daily articles") are turned on in your settings. Also, if you use Gmail to read email, please check to make sure the emails aren't in your social or promotions tabs. If they are, please drag them over to the primary tab to ensure they end up there in the future.
If the daily articles box is already checked, please try adding email@example.com, firstname.lastname@example.org and email@example.com (the email addresses our emails come from) as safe senders/contacts (or see if your company IT department can whitelist them).
If article emails are turned on, you've made sure we're considered a safe sender, and you're still not receiving emails, please contact firstname.lastname@example.org.