Reply To: 500 Internal Server Error on admin page

Hi,

500 Internal Error is a generic error and says about some issue on the server and can be caused by different things. Anyway, to understand its nature you need to see your server error logs or enable PHP error display on the website. If you can’t do this, you need to contact your hosting provider for help with this question. Here is an article that may help you understand the error better http://www.wpbeginner.com/wp-tutorials/how-to-fix-the-internal-server-error-in-wordpress/
If you want to return your money back, you can request a refund here https://themeforest.net/refund_requests/new

Regards