Fatal Error

My site, made using savona blog, was running fine and then instantly a fatal error came and it stopped working. Seems like syntax error but can’t find the solution. Savona Support not responding. Error is:

Fatal error: Cannot redeclare savona_true_false() (previously declared in /home3/waferswi/public_html/wp-content/themes/savona/inc/customizer/dynamic-css.php:13) in /home3/waferswi/public_html/wp-content/themes/savona/inc/customizer/dynamic-css.php on line 13

The page I need help with: [log in to see the link]