The error happened when updating to 1.4.3 of your plugin (currently at 1.4.3 but deactivated), WordPress version is 5.8.1, the theme is a child theme of Materialis Pro.
Plugins: Advanced Custom Fields; Advanced Editor Tools; All in One SEO; All-in-One WP Migration; Breadcrumb NavXT; Classic Editor; Materialis Companion; Media from FTP; Page scroll to id; Pods; Polylang (3.1.1); Really Simple SSL; Show Current Template; Smush; Velvet Blues Update URLs; Wordfence Security; WP Sitemap Page.
Thanks!