Delete the transactions. The available registration spaces will be re-added to Blackbaud NetCommunity as an available registration.
For unprocessed event registrations that are in the Blackbaud NetCommunity that can be deleted:
For already processed event registrations:
1. In The Raiser's Edge, click Records, Events.
2. Open the event record.
3. Selects the Participants tab and delete any incorrect or unnecessary registrations. The event registration will be re-added to Blackbaud NetCommunity as an available event registration. The event registration block/unavailability will be removed and will become active for registrations.