Website reverting to old versions / not updating

I have a weird problem where my website's content won't update, and sometimes decides to revert back to old versions from over a 1/2 weeks ago.

The URL I'm working on is http://voddr.com/r2/ - this is a web based mobile application using Lungo JS framework. When you go onto it, you should see a login screen and there shouldn't be any menu button in the top left. If you fill out the username and password form, then hit register, it should sign you up and take you to a different page with multiple buttons including a logout button.

Note that you will have to put this into responsive mode if you decide to test for yourself (iPhone view preferrably)

I made this login system etc over 2 weeks ago, and a few days ago when I last checked it was all working. Now on the same machine, days later, it has reverted back to a previous version before I created the login system.

Now when I go onto the site there's a menu button in the top left, which shouldn't show up until you register or sign in, and when I try using the login/register system it doesn't do anything. A further inspection into the code using Chrome developer tools shows that it has reverted back to the old code from weeks ago.

I am working on this by editing in Notepad++ then file transfer via FTP.

I have tried using CTRL + F5 to force refresh cache, and I also have a browser plugin which will entirely clear data for a site, including local storage/database etc.

I have also transferred all the files across again, still no luck. I have triple checked that I'm uploading to the right place, and uploading the correct files, so that's not the problem.

What would you suggest I try out? If anyone wants any more info I have missed let me know.

Thanks!