How to change dynamically event by start and end date in FullCalendar?

Question

function myFunction(check_in_time,check_out_time) {   
 $('#calendar').fullCalendar({
       events: [
        {
            title: 'Check-In-Out-Date',
            start: check_in_time,
            end: check_out_time,
            allDay: true
        }
       ],
     });
}

I am using ajax function to call myFunction(check_in_time,check_out_time) every-time when I clicked on some button. It changes only first time. I need my calendar to change event every-time when myFunction(check_in_time,check_out_time) called. How to Improve my code? Thanking you.