I’m having the same problem, in the past week, likely since an upgrade, I stopped getting notification emails from the form at brooks-malone.com. We used to have them sent to the email addresses for my client and myself as a backup.
UPDATE: It appears that recent upgrades have had a lot of new notification functionality added, which is cool! But, it wiped out my old notification instructions. You need to recreate these. From the admin console, choose Forms > Forms and Submissions. Then for each form in your list, choose to edit the form. On the edit screen, in the top left corner click the blue Manage Form button.Then on the Form Settings screen, scroll to the bottom to the notifications area. Choose to add a notification, and setup your notification. Make sure to set Activate Notification to “Yes”. This fixed my problem and I started getting notifications again.