Hi there!
ACF Support Team here, Thanks for reaching out with your query we would be happy to assist
ACF plugin is fully compatible with PHP versions 8.0 and 8.1. However, your code might not be, so we recommend testing PHP 8 version in a staging environment to ensure everything works as expected before upgrading live environments.
Can you please enable DEBUG_MODE and WP_DEBUG_LOG which will allow errors to be logged into the file ‘/wp-content/debug.log’
Here is some code to add to your wp-config.php file which will enable these constants:
define('WP_DEBUG', true);
define('WP_DEBUG_DISPLAY', false);
define('WP_DEBUG_LOG', true );
Try running the accessing the site again and check what the errors say.
If you need further clarification, please create a ticket using our ?support form and we can look into it further.
