Fatal error

Hello, I’m trying to use this theme but every time I activate it, I get the following error. Anyone have any suggestions?

Fatal error: Uncaught Error: Call to undefined method fortune_backward_version_compatiblity::fortuneBackwardCompForSlider() in /home/madisonfire/MadisonFire.com/site/wp-content/themes/fortune/functions/fortune-functions.php:703 Stack trace: #0 /home/madisonfire/MadisonFire.com/site/wp-content/themes/fortune/functions/fortune-functions.php(743): fortune_backward_version_compatiblity->__construct() #1 /home/madisonfire/MadisonFire.com/site/wp-content/themes/fortune/functions.php(15): include(‘/home/madisonfi…’) #2 /home/madisonfire/MadisonFire.com/site/wp-settings.php(497): include(‘/home/madisonfi…’) #3 /home/madisonfire/MadisonFire.com/site/wp-config.php(96): require_once(‘/home/madisonfi…’) #4 /home/madisonfire/MadisonFire.com/site/wp-load.php(37): require_once(‘/home/madisonfi…’) #5 /home/madisonfire/MadisonFire.com/site/wp-blog-header.php(13): require_once(‘/home/madisonfi…’) #6 /home/madisonfire/MadisonFire.com/site/index.php(17): require(‘/home/madisonfi…’) #7 {main} thrown in /home/madisonfire/MadisonFire.com/site/wp-content/themes/fortune/functions/fortune-functions.php on line 703

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