Phantomjs cookie authentication failed to capture and print the web page - cookies

Question

I am using phantomjs to print the webpage and create a pdf. As the UI needs the user's authentication before finding the data, I used persistent cookies to authenticate the user. But somehow I got login screen every time in the created PDF. I observed that the user authenticated successfully and also the result's webpage showing proper result (debug logs showing the proper data array) but while printing the web page or creating a PDF, it somehow gets the login screen. Sometimes I observed that I got two different cookies in my PHP code while getting the report data and in javascript 'document.cookies'.
Please let me know how can I fix this.
var page = require('webpage').create(),
system = require('system'), t, address;
page.settings.userName = 'myusername';
page.settings.password = 'mypassword';
if (system.args.length === 1) {
console.log('Usage: scrape.js ');
phantom.exit();
} else {
t = Date.now();
address = system.args[1];
page.open(address, function (status) {
if (status !== 'success') {
console.log('FAIL to load the address');
} else {
t = Date.now() - t;
var title = page.evaluate(function() { return document.title;})
console.log('Page title is ' + title);
console.log('Loading time ' + t + ' msec');
}
phantom.exit();
});
}
Another piece of code of sending a cookie file
bin/phantomjs --cookies-file=/tmp/cookies.txt --disk-cache=yes --ignore-ssl-errors=yes /phantomjs/pdf.js 'username' 'params' '/tmp/phantomjs_file' /tmp/phantom_pdf.pdf
And
phantomjs --cookies-file=cookies.txt examples/rasterize.js localhost:7000/reports /tmp/report.pdf