When a new ticket is created then it sends a alert message to Admin Email, Department Manager and Department Members.
Enabling New Ticket Alert does not work for Organization Account Manager.
go to Admin panel -> Settings -> Alerts & Notices -> New Ticket Alert and check
go to Admin panel -> Staff -> Department -> YOUR DEPARTMENT and check "New Ticket"
go to Admin panel -> Emails -> Template -> New Ticket Alert and check
Restart server. It works fine.