I used node-schedule module to cron a job executed only once at particular time. I also use callable function to trigger Cloud Function and to get client-side data. The big trouble is that all things are fine to cron a single task until 15 minutes. But, on the other hand it doesn't do the task scheduled further time more than 15 minutes. What may occur after 15 minutes to cancel task? I used Firebase Quickstart code and I add only schedule-job module into the code. I didn't changed anything other than getting scheduling time values from client-side. I really need help for this issue. The cloud function script and my stack overflow post here Thank you.