Spectrum Theme Fatal Error After Installation

wordpress
themeforest

#1

after the activation of the template, find this error:

​Fatal error: Call to a member function put_contents() on a non-object in /web/htdocs/www.folkit.it/home/wp-content/themes/wp_spectrum/functions.php on line 104​

How can I fix the problem?​

thanks for collaboration​

Federico Romano