Error when saving the post

Site https://consultport.com/ from time to time have erorr messages while we saving posts. Here is one of such messages.

“Since WordPress 5.2 there is a built-in feature that detects when a
plugin or theme causes a fatal error on your site, and notifies you
with this automated email.

In this case, WordPress caught an error with one of your plugins, Yoast SEO.

First, visit your website (https://consultport.com/) and check for any
visible issues. Next, visit the page where the error was caught
(https://consultport.com/wp-admin/post.php?post=23402&action=trash&_wpnonce=312545e3ea)
and check for any visible issues.
…

When seeking help with this issue, you may be asked for some of the
following information:
WordPress version 5.9.3
Current theme: Avada Child (version 1.0.0)
Current plugin: Yoast SEO (version 18.9)
Yoast SEO Premium (version 18.4)
PHP version 7.4.28

Error Details
=============
An error of type E_ERROR was caused in line 102 of the file
/home/wp/disk/wordpress/wp-content/plugins/wordpress-seo/src/builders/indexable-hierarchy-builder.php.
Error message: Uncaught TypeError: Argument 1 passed to
Yoast\WP\SEO\Builders\Indexable_Hierarchy_Builder::build() must be an
instance of Yoast\WP\SEO\Models\Indexable, bool given, called in
/home/wp/disk/wordpress/wp-content/plugins/wordpress-seo/src/integrations/watchers/indexable-ancestor-watcher.php
on line 198 and defined in
/home/wp/disk/wordpress/wp-content/plugins/wordpress-seo/src/builders/indexable-hierarchy-builder.php:102
Stack trace:
#0 /home/wp/disk/wordpress/wp-content/plugins/wordpress-seo/src/integrations/watchers/indexable-ancestor-watcher.php(198):
Yoast\WP\SEO\Builders\Indexable_Hierarchy_Builder->build()
#1 [internal function]:
Yoast\WP\SEO\Integrations\Watchers\Indexable_Ancestor_Watcher->update_hierarchy_and_permalink()
#2 /home/wp/disk/wordpress/wp-content/plugins/wordpress-seo/src/integrations/watchers/indexable-ancestor-watcher.php(127):
array_walk()
#3 /home/wp/disk/wordpress/wp-includes/class-wp-hook.php(307):
Yoast\WP\SEO\Integrations\Watchers\Indexable_Ancestor_Watcher->reset_children()
#4 /hom”

Please let us know what’s the problem.
Thanks.
Regards, Yurii

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