Notification user preferences show that Email device is disabled but in table [cmn_notif_message] has fields 'Send Email' enabled
To reproduce, set in [cmn_notif_message] table, the field 'Send Email' to "False" for device 'Primary Email' and for a specific user, and for specific notification.
Check that user preferences in the UI for that logged in user and specific notification still show up as true.
The table [cmn_notif_message] has fields 'Send Email' and 'Send SMS' but they are not used. These are legacy fields.
To disable a specific notification for the a user, set 'filter' field to value to "Unsubscribe" in list view of table [cmn_notif_message] filtering by user and device. To re-enable it, you can see the 'filter' field value to "" (empty).