You have the option to Cancel your event and add a specific cancellation reason if you want to.
In order to cancel your event, navigate to your Administration panel, and under Live Sessions/In-Class Training select Manage Events.
Find the event in question, click on the Manage Event option, and then select Cancel.
In the pop-up window that arises add the cancellation reason and hit Cancel event.
You will then be able to find all of the events that were cancelled along with the relevant cancellation reason simply by using the filtering options.
In case that you have canceled an offer included in an event-bundle, several recalculations will take place, based on the attendance rules that you had set during the event-bundle creation.