Fatal error: Cannot declare class WP_Metadata_Lazyloader, because the name is already in use in /customers/a/5/8/kiwispas.co.uk/httpd.www/wp-includes/class-wp-metadata-lazyloader.php on line 32

Fatal error: Uncaught Error: Class "WP_Translation_Controller" not found in /customers/a/5/8/kiwispas.co.uk/httpd.www/wp-includes/l10n.php:800
Stack trace:
#0 /customers/a/5/8/kiwispas.co.uk/httpd.www/wp-includes/l10n.php(959): load_textdomain('default', '/customers/a/5/...', 'en_US')
#1 /customers/a/5/8/kiwispas.co.uk/httpd.www/wp-includes/class-wp-fatal-error-handler.php(49): load_default_textdomain()
#2 [internal function]: WP_Fatal_Error_Handler->handle()
#3 {main}
  thrown in /customers/a/5/8/kiwispas.co.uk/httpd.www/wp-includes/l10n.php on line 800