Go try syncing some items at the demo board.
CardSync is being frozen. All existing paying accounts will continue to work, but no new users will be allowed to add syncs.
Sorry about this, but we're being forced to this by the new limits on the number of boards a user can have Trello is imposing.
We suggest that you try out Cardsync for Teams, a Trello Power-Up with the same functionality of this bot, but a much better interface. In the future we may create a new Power-Up, not specifically tied to Trello teams, but following the Power-Up model of Cardsync for Teams, as it will not be affected by this nor by future restrictions imposed on the Trello Platform.