Move method into group

app/mailers/notify.rb

@@ -82,7 +82,7 @@ class Notify < BaseMailer
     group_notification_email = nil
 
     if notification_group
-      notification_settings = notification_group.notification_settings(hierarchy_order: :asc).where(user: @current_user) # rubocop: disable CodeReuse/ActiveRecord
+      notification_settings = notification_group.notification_settings_for(@current_user, hierarchy_order: :asc)
       group_notification_email = notification_settings.find { |n| n.notification_email.present? }&.notification_email
     end
 

app/models/group.rb

@@ -138,6 +138,10 @@ class Group < Namespace
       .order("ordered_groups.depth #{hierarchy_order}")
   end
 
+  def notification_settings_for(user, hierarchy_order: nil)
+    notification_settings(hierarchy_order: hierarchy_order).where(user: user)
+  end
+
   def to_reference(_from = nil, full: nil)
     "#{self.class.reference_prefix}#{full_path}"
   end