Node JS cron function triggering multiple times

Question

I like to run some set of async codes (eg. push notifications) for every one hour. But it's firing my function 2 times, 3 times randomly. But I need to fire that function only for one time for an hour.

My code given below

        var Job = new CronJob({
        cronTime: '0 * * * *',
        onTick : _.throttle(function() {
            //my_function
        }, 2000, { leading: true, trailing: false })
        start   : true,
        timeZone: 'Asia/Kolkata'
        });

Please help me with this. Thanks in advance