The "email" is missing.
Fatal error: Uncaught Error: Call to a member function createSubscription() on null in /srv/users/serverpilot/apps/restaurantesdelaciudad/public/wp-content/plugins/php-code-for-posts/Classes/Shortcode.php(81) : eval()'d code:28 Stack trace: #0 /srv/users/serverpilot/apps/restaurantesdelaciudad/public/wp-content/plugins/php-code-for-posts/Classes/Shortcode.php(81): eval() #1 /srv/users/serverpilot/apps/restaurantesdelaciudad/public/wp-content/plugins/php-code-for-posts/Classes/Shortcode.php(38): PhpCodeForPosts_Shortcode::do_shortcode(Object(PhpCodeForPosts_Snippet), Array) #2 /srv/users/serverpilot/apps/restaurantesdelaciudad/public/wp-includes/shortcodes.php(345): PhpCodeForPosts_Shortcode::handle_shortcode(Array, '', 'php') #3 [internal function]: do_shortcode_tag(Array) #4 /srv/users/serverpilot/apps/restaurantesdelaciudad/public/wp-includes/shortcodes.php(223): preg_replace_callback('/\\[(\\[?)(php)(?...', 'do_shortcode_ta...', '<p>[php snippet...') #5 /srv/users/serverpilot/apps/restaurantesdelaciudad/public/wp-inclu in /srv/users/serverpilot/apps/restaurantesdelaciudad/public/wp-content/plugins/php-code-for-posts/Classes/Shortcode.php(81) : eval()'d code on line 28