Fatal Error

Just tried an update and got the following message: Fatal error: Cannot declare class WP_Block_Styles_Registry, because the name is already in use in /homepages/29/d754797892/htdocs/clickandbuilds/phoebeandisabella/wp-content/plugins/gutenberg/lib/class-wp-block-styles-registry.php on line 14 Any help much appreciated. Cheers, Paul.