WordPress Add New Post shows this "Warning: Attempt to read property "post_type" on null in /var/www/html/blog/wp-includes/post.php on line 7589"

I recently migrated my website to new AWS ec2 linux instance. Php8.0, MySql8.0, all pages work fine. WordPress database was exported from Mysql5.7 and imported to MySql8.0. The blog display and other parts of WordPress works fine. But when I click ‘Add New Post’ I am getting these errors. WordPress is latest 5.9.3.

Warning: Attempt to read property "post_type" on null in /var/www/html/blog/wp-includes/post.php on line 7589

Warning: Attempt to read property "post_type" on null in /var/www/html/blog/wp-includes/post.php on line 7590

Warning: Attempt to read property "ID" on null in /var/www/html/blog/wp-includes/post.php on line 7594

Warning: Attempt to read property "post_type" on null in /var/www/html/blog/wp-includes/post.php on line 7837

Warning: Attempt to read property "post_type" on null in /var/www/html/blog/wp-includes/theme.php on line 3502

Warning: Attempt to read property "post_type" on null in /var/www/html/blog/wp-content/mu-plugins/endurance-page-cache.php on line 544

Warning: Attempt to read property "public" on null in /var/www/html/blog/wp-content/mu-plugins/endurance-page-cache.php on line 544

Warning: Attempt to read property "ID" on null in /var/www/html/blog/wp-content/plugins/jetpack/jetpack_vendor/automattic/jetpack-sync/src/modules/class-posts.php on line 557

Warning: Attempt to read property "post_type" on null in /var/www/html/blog/wp-includes/theme.php on line 3727

Warning: Attempt to read property "post_type" on null in /var/www/html/blog/wp-includes/post.php on line 5375

Warning: Attempt to read property "ID" on null in /var/www/html/blog/wp-includes/post.php on line 5375

Warning: Attempt to read property "post_type" on null in /var/www/html/blog/wp-includes/post.php on line 4676

Fatal error: Uncaught Error: Attempt to assign property "post_content" on null in /var/www/html/blog/wp-admin/includes/post.php:742 Stack trace: #0 /var/www/html/blog/wp-admin/post-new.php(66): get_default_post_to_edit('post', true) #1 {main} thrown in /var/www/html/blog/wp-admin/includes/post.php on line 742

If I disable the errors in my.conf the page goes into an endless loop and finally displays ‘Gateway Timeout’.