Thanks for sharing the website URL. I can see few error messages on browser console.
Access to Font at 'http://akademisiroh.com/aksi/wp-content/themes/pro/framework/fonts/font_awesome/fontawesome-webfont.woff2?v=4.7.0' from origin 'http://www.akademisiroh.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://www.akademisiroh.com' is therefore not allowed access. https://screencast.com/t/XD6CDaae
Please refer following article to resolve the problem: https://theme.co/apex/forum/t/troubleshooting-font-awesome/200
Next, using FTP please navigate to /wp-content/themes/ directory and then rename existing Pro directory. Now try and see if you can login to WordPress backend. If the login is working fine, please download the latest version of Pro Theme and then upload the files. You can also upload the Pro theme file using FTP in /wp-content/themes/ directory. We have released a new maintenance release that has bunch of bug fixes. You can review that on our changelog page https://theme.co/changelog/.
IF you don't have FTP details, you can get the same from your hosting provider.
Let us know how it goes.