If you are experiencing problems with your site after updating to WordPress 5.6, then it might help if you install the jQuery Migrate Helper plugin: https://wordpress.org/plugins/enable-jquery-migrate-helper/, and set the version to legacy 1.12.4. The problems could include missing sliders, or mobile menus for example.
Edit: temporary solution for resolving the empty mobile menu when using an alternate menu for mobile; replace /enfold/includes/helper-main-menu.php, with this file: https://www.dropbox.com/s/6gmyfwwcicl0mdi/helper-main-menu.php?dl=0