author of WP Native Articles here. This is normally a problem with other plugins incorrectly messing around with tag incorrectly and preventing it from setting the correct URL. If you save this code below as a separate file, upload it as a plugin and activate it it should fix it.
<?php
/**
* Plugin Name: WPNA Editor Fix
* Description: Fix the base URL meta field that other plugins break.
* Author: OzTheGreat (WPArtisan)
* Author URI: https://wpartisan.me
* Version: 1.0.1
* Plugin URI: https://wp-native-articles.com
*
* @package wpna-editor-fix
*/
add_action( 'admin_footer-post.php', 'wpna_custom_fix_base_url' );
add_action( 'admin_footer-post-new.php', 'wpna_custom_fix_base_url' );
function wpna_custom_fix_base_url(){
?>
<script>
if ( window.history.replaceState ) {
var bases = document.getElementsByTagName('base');
if (bases.length > 0) {
bases[0].href = document.getElementById( 'wp-admin-canonical' ).href + window.location.hash;
}
}
</script>
<?php
}