This plugin adds a new tab to WordPress' site health page with various transients and options which can help debug ACF update issues. It also can help diagnose issues between caches and database values for important WordPress option values.
If you're installing this, you've probably been asked to send the info over to support@advancedcustomfields.com. Specifically, the output visible on the page <site_url>/wp-admin/site-health.php?tab=acf-update