Issue with Primary key duplicate entries on all wp_meta table

Hi,

I have been having multiple issues, with my website, which I think can be traced to multiple primary key entries on all my main ‘meta tables’ i.e
wp_commentmeta, wp_postmeta, wp_usermeta. Some of the issues include;

Admin having the ‘submit for revision’ button instead of the ‘post’ button when creating a new post.
Not being able to customize themes.
‘Comments Pending Approval’ showing that there are comments awaiting approval, but none appear when you open the tab.
Not being able to upload media files (images) on posts.

My error log has repetitions of the following line;

‘WordPress database error Duplicate entry ‘0’ for key ‘PRIMARY’ for query INSERT INTO wp_postmeta (post_id, meta_key, meta_value) VALUES (4215, ‘_oembed_time_4480386210e25763d57c6945cf5a7121’, ‘1613052884’) made by require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), include(‘/themes/twentytwentyone/archive.php’), get_template_part, locate_template, load_template, require(‘/themes/twentytwentyone/template-parts/content/content-excerpt.php’), get_template_part, locate_template, load_template, require(‘/themes/twentytwentyone/template-parts/excerpt/excerpt.php’), the_excerpt, get_the_excerpt, apply_filters(‘get_the_excerpt’), WP_Hook->apply_filters, wp_trim_excerpt, apply_filters(‘the_content’), WP_Hook->apply_filters, WP_Embed->autoembed, preg_replace_callback, WP_Embed->autoembed_callback, WP_Embed->shortcode, update_post_meta, update_metadata, add_metadata
[11-Feb-2021 14:18:05 UTC] PHP Warning: require(/home/osbkecom/public_html/wp-includes/author-template.php): failed to open stream: No such file or directory in /home/osbkecom/public_html/wp-settings.php on line 182
[11-Feb-2021 14:18:05 UTC] PHP Fatal error: require(): Failed opening required ‘/home/osbkecom/public_html/wp-includes/author-template.php’ (include_path=’.:/opt/cpanel/ea-php72/root/usr/share/pear’) in /home/osbkecom/public_html/wp-settings.php on line 182′

Any ideas on how to fix this?

The page I need help with: [log in to see the link]