node-schedule job does not working in function - node.js

Question

I am trying to work with node-schedule. I want to create a dynamic scheduler. I want to set rule for schedule dynamically. Its working fine when it is called as per the documentation on github. But when I take it in a function through loop then its not working. My code is given below. In code smtp email address has been modified for security purpose.
con.connect(function (err) {
if (err) throw err;
con.query("SELECT * FROM customers", function (err, result, fields) {
if (err) throw err;
for (var i = 0, len = result.length; i < len; i++) {
var dt = dateTime.create(result[i].expire_date);
var formattedDate = dt.format('Y-m-d');
if (result[i].payment_status === 0) {
var dt_str = formattedDate.split('-');
var dt_year = parseInt(dt_str[0]);
var dt_month = parseInt(dt_str[1]);
var dt_date = parseInt(dt_str[2]);
var mail_to = result[i].email, mail_sub='Schedule Of Maintenance', mail_message='Test Mail message Status';
console.log('ScheduleCron Function calling');
scheduleCron(dt_date,dt_month, dt_year, mail_to, mail_sub, mail_message);
} else {
console.log(result[i].payment_status);
}
}
});
});
function scheduleCron(schedule_date,schedule_month,schedule_year,mail_to,mail_sub,mail_message) {
console.log(schedule_date+' '+schedule_month+' '+schedule_year);
console.log('ScheduleCron Function In');
var date = new Date(schedule_year, schedule_month, schedule_date, 13, 33, 0);
schedule.scheduleJob(date, function(){
sendEmail( mail_to, mail_sub, mail_message);
});
}
function sendEmail(mail_to,mail_sub,mail_message) {
var mailOptions = {
from: "email#gmail.com",
to: mail_to,
subject: mail_sub,
text: mail_message
};
transporter.sendMail(mailOptions, function (error, info) {
if (error) {
throw error;
} else {
console.log("Email successfully sent!");
}
});
}

Answer 1

You need to create a job object as you see in documentation https://www.npmjs.com/package/node-schedule
const job = schedule.scheduleJob(date, function(){
sendEmail( mail_to, mail_sub, mail_message);
});
}

Answer 2

You are missing the Job object which is required by the scheduling algorithm.
From the documentation
Jobs and Scheduling
Every scheduled job in Node Schedule is represented by a Job object. You can create jobs manually, then execute the schedule() method to apply a schedule, or use the convenience function scheduleJob() as demonstrated below.

Answer 3

I was confused by this too. I couldn't understand why this wasn't working, I mean "myFunc()" is a function. right? So you throw myFunc() into the second argument of scheduleJob():
function myFunc(){
console.log("stuff");
do.otherStuff();
}
schedule.scheduleJob('*/10 * * * *', myFunc());
But for some strange reason, it has to be called like this:
function myFunc(){
console.log("stuff");
do.otherStuff();
}
schedule.scheduleJob('*/10 * * * *', function(){
myFunc();
});
to avoid the TypeError: this.job.execute is not a function error when it executes.