When you are trying to delete an event type, you get the error message 'Event Type delete is only possible when there are no events of that type.' as shown on below screenshot.
Solution
This is expected behavior, you cannot delete an event type if there are existing events for this event type.
You need to delete the event/events which is/are associated with the event type, only then you are able to delete the event type. For that, you need to use GET events API with the filter value to know the number of events associated with the event type. For more details, please visit the below MindSphere documentation URL:
Notes