Post gets vacant after few days

Hi,

I have created my website using WordPress 3.8.4. Now I am facing a problem that one of the post always gets vacant automatically. I write the contents to that particular post but it always get vacant after few days. Even rest of the other posts remain same but only one post get vacant. Can you suggest any possible cause and solution?

link is : https://www.twxholidays.com/index.php/amarnath-yatra-by-helicopter-3n-4d/

Regards,

Matt