Cannot get Id of the moved event in onEventMoved

When I move an event in the onEventMoved I cannot get the ID of the event. It is a function.

function eventMoved(args) {
console.log('Moved event', args);

api.one('reservations/scheduler/event', args.e.id).get().then(function (response) {
//args.e.id is function instead of an integer/object
//do something
})
}

How to get the ID