I am using a free version of the plugin and it has not been working since the past 2-3 days. I see that there have been some new version releases in the last 2 days and I am wondering if that is causing the issue. the booking calendar is working fine in the preview page but not on the live published page. you can check here: http://smileferry.com/book-your-home-visit/
Kindly let me know the fix.