Warning: require_once(vendor/autoload.php): Failed to open stream: No such file or directory in /customers/f/b/f/feuxsaintjean.be/httpd.www/wp-content/plugins/feuxsaintjean-query/feuxsaintjean-query.php on line 18

Fatal error: Uncaught Error: Failed opening required 'vendor/autoload.php' (include_path='.:/usr/share/php') in /customers/f/b/f/feuxsaintjean.be/httpd.www/wp-content/plugins/feuxsaintjean-query/feuxsaintjean-query.php:18
Stack trace:
#0 /customers/f/b/f/feuxsaintjean.be/httpd.www/wp-settings.php(517): include_once()
#1 /customers/f/b/f/feuxsaintjean.be/httpd.www/wp-config.php(101): require_once('/customers/f/b/...')
#2 /customers/f/b/f/feuxsaintjean.be/httpd.www/wp-load.php(50): require_once('/customers/f/b/...')
#3 /customers/f/b/f/feuxsaintjean.be/httpd.www/wp-blog-header.php(13): require_once('/customers/f/b/...')
#4 /customers/f/b/f/feuxsaintjean.be/httpd.www/index.php(17): require('/customers/f/b/...')
#5 {main}
  thrown in /customers/f/b/f/feuxsaintjean.be/httpd.www/wp-content/plugins/feuxsaintjean-query/feuxsaintjean-query.php on line 18