use ensure_reg_number_seq

app/models/csv_db.rb

@@ -16,7 +16,7 @@ class CsvDb
           errors.push({ member_id: row[0], email: row[9], errors: user.errors.full_messages })
         end
       end
-      organization.update(reg_number_seq: (organization.members.maximum(:member_uid)))
+      organization.ensure_reg_number_seq!
       errors
     end
   end

app/views/admin/csv/upload_csv.html.haml

@@ -1,4 +1,4 @@
-= form_for :dump, :url=>{:action=>"import_csv"}, :html => { :multipart => true, class: "formtastic user"} do |f|
+= form_for :dump, url: {action: "import_csv"}, html: { :multipart => true, class: "formtastic user"} do |f|
   %fieldset.inputs
     %ol
       %li.string.input.optional.stringish
@@ -7,7 +7,7 @@
     %ol
       %li.string.input.optional.stringish
         = label_tag I18n.t("active_admin.users.organization")
-        = f.select :organization_id, options_for_select(Organization.all.map{ |org| [org.name, org.id] }), {}, { id: "select2", required: true }
+        = f.select :organization_id, options_for_select(Organization.all.map{ |org| [org.name, org.id] }), include_blank: true
 
   %fieldset.actions
     %ol