I need help in using the join function in JQL

Hello,

I'm trying to run this query:

function main() { 
	return join( 
		Events({ 
   			from_date: "2020-04-10",
    			to_date: "2020-06-10"
		}), 
  		People(), 
		{
			type:'inner',
			selectors:[{event:"[Login] Log in success"}]
		})
		.groupByUser(function(state, events){
                        return events
                })
}

The output is something like this:

[
{
"key": [
"sdssdfsdfsdfsdfsd"
],
"value": [
{
"distinct_id": "sdfsfsdfsdfsdfsdf",
"event": {},
"labels": [],
"user": {
"distinct_id": "sdfdsfsdfsfsfsdfdsf",
"labels": [],
"last_seen": 1589181171754,

It's not clear to me why I'm getting "event":{}

Why is there no event information?