maybe im wrong, but all my sonata services has the first argument null, second the entity and third the controller...
I think your service must be:
services:
sonata.admin.card:
class: MyConpany\BlaBlaBundle\Admin\CardAdmin
tags:
- { name: sonata.admin, manager_type: orm, group: Cards, label: "Cards" }
arguments: [null, MyConpany\BlaBlaBundle\Entity\Card, BLBundle:Card ]the last argument (BlBundle:Card ) refers to MyConpany\BlaBlaBundle\Controller\CardController file