Error warnings

Hi, I have some warning messages on my wordpress website after apdating my wordpress to the latest version, it only becomes ok when I restore my backup before the update. Here are the messages; please assist

Warning: call_user_func_array() expects parameter 1 to be a valid callback, function '_disable_block_editor_for_navigation_post_type' not found or invalid function name in /home/customer/www/ikahengacademy.co.za/public_html/wp-includes/class-wp-hook.php on line 307

Warning: Cannot modify header information - headers already sent by (output started at /home/customer/www/ikahengacademy.co.za/public_html/wp-includes/class-wp-hook.php:307) in /home/customer/www/ikahengacademy.co.za/public_html/wp-content/plugins/sg-cachepress/core/Supercacher/Supercacher_Helper.php on line 86

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