If your customer says that they aren't receiving emails, the first step is double-check that the email failed to send.
If you navigate to the Notification list page in the merchant portal, you can view all your "Failed" notifications by clicking on the "Failed" filter at the top.
If there's a specific notification that you're looking for, you can even search for the email address in question.
Once you can confirm that the system has marked the notification as failed, it's time to figure out why exactly that notification failed to send. The two most common cases for a notification:
The Customer Entered the Wrong Email
Often times, customers will mis-type a single character in their email address. For example, "gmail.con" should obviously be "gmail.com"
Many slight changes to an email like this account for the majority of failed notifications.
The Customer's Email Server Rejected the Notification
Sometimes, the customer's email server might be down for maintenance for an extended period of time. This causes notifications to be marked as failed since we can't get the message to the customer.
If you suspect this is the case, check the notification logs for the customer to figure out if any notifications have been successfully delivered to that email address, previously.
Still not sure why the customer didn't get the notification?
Feel free to shoot an email to our support team (firstname.lastname@example.org) and they can look up the exact reason the notification could not be delivered (make sure to let them know what notification you're wondering about)