If you wish to disable approval notification for all users of change application, you can try doing it in other way.
Quick links -> Approval Administration Console -> Notification Tab, look for records for Change related processes and you can set it to 'Inactive'. This will disable approval notification for change application. You can directly open AP:Notification form and check for change related records and modify status to 'Inactive'.
These are the records which are responsible to trigger notifications from Approval Server which later handled by ITSM workflows and notification emails being sent as a end result.
Thanks, but I need to disable the notification precisely for one person.
can you show screenshot of notiication preference from user people profile?
can you try below: Open below filter
Change mapping of below field
Notification Type = "People Support Staff"
Save the filter and test again
It i not working because notification type is set to "People"
When it is set to People mean this notification is sent to customer where there is possibility that customer may not have login id and notification preference and bedefault email is sent to that user.
When Notification Type = "People Support Staff" which is considered as support staff notification where login id should be available and in this case notification preference is validated.
So would suggest you to contact support and get defect id which will fix this issue in next release and you can this workaround for now.