Warning: require_once(compatibility/acf.php): Failed to open stream: No such file or directory in /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-content/plugins/relevanssi-premium/lib/init.php on line 526

Fatal error: Uncaught Error: Failed opening required 'compatibility/acf.php' (include_path='.:/usr/share/pear:/usr/share/php') in /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-content/plugins/relevanssi-premium/lib/init.php:526
Stack trace:
#0 /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-content/plugins/relevanssi-premium/lib/init.php(163): relevanssi_load_compatibility_code()
#1 /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-includes/class-wp-hook.php(324): relevanssi_init('')
#2 /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array)
#3 /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#4 /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-settings.php(727): do_action('init')
#5 /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-config.php(213): require_once('/home/httpd/vho...')
#6 /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-load.php(50): require_once('/home/httpd/vho...')
#7 /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-blog-header.php(13): require_once('/home/httpd/vho...')
#8 /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/index.php(17): require('/home/httpd/vho...')
#9 {main}
  thrown in /home/httpd/vhosts/baukulturschweiz.ch/httpdocs/wp-content/plugins/relevanssi-premium/lib/init.php on line 526