Add cancan permissions for Admin::ManagerInvitationsController

app/controllers/admin/manager_invitations_controller.rb

@@ -1,5 +1,7 @@
 module Admin
   class ManagerInvitationsController < Spree::Admin::BaseController
+    authorize_resource class: false
+
     def create
       @email = params[:email]
       @enterprise = Enterprise.find(params[:enterprise_id])

app/models/spree/ability_decorator.rb

@@ -127,6 +127,8 @@ class AbilityDecorator
     can [:admin, :connect, :status, :destroy], StripeAccount do |stripe_account|
       user.enterprises.include? stripe_account.enterprise
     end
+
+    can [:admin, :create], :manager_invitation
   end
 
   def add_product_management_abilities(user)