Event cancellation is irreversible, and once it's done, you cannot undo the process.
When an event is canceled, a cancellation notice will be sent to all guests. If you want to host an event on the same day at the same time with the same guests, you have to re-register an event date and then ask your guests to book the event again via group messaging.
By setting the booking deadline and cancellation deadline right before the event's starting time, the re-registration of the event date will be much easier.