We have checked out your Website and it returns a 500 Internal Server Error which indicates that this is a Server Issue.
Firstly, please make sure that your PHP Version is more than 5.6 or preferably the Latest Version.
Secondly, as you are trying to use SMTP, first make sure that your SMTP Servers are up and running. The Password indicated is indeed for the Email Password.
If you are still facing further issues, then please consider adding the .customjs Class to the .form-widget DIV and then the following code at the very top (just after the php open tag) of your include/form.php File:
[ch_pre type="php"]error_reporting(E_ALL);[/ch_pre]
which should display all the possible errors. Please notify us about the Error Message you see, after going through the process above, so that we can provide you with more assistance on this.