my htaccess file is being corrupted again and again

I am running my site on wordpress. Recently I have changed the hosting company and now using hostgattor for hosting. After migrating the site to new host, my site is giving 500 internal server error again and again. As a solution, I renamed the old htaccess file and created a new one. The error is gone but just for a few days. After some time, it again starts showing 500 internal server error. As a quick fix, I create a new htaccess file and the issue is resolved temporarily. It seems that my htaccess file is being corrupted somehow. Please provide some permanent solution.