“acf/load_field” Critical error upon saving/updating WooCommerce products [closed]

The error is indicating that a method function (get_attribute()) is attempting to be called on a variable that is set to null. This means that the $product_object variable is not populated with an instance of a class that has a method definition for get_attribute(), but rather is null.

You’ll need to figure some other way to get the current product object. If you’re in the admin editing a product, then you can get the product ID from a query parameter, and create the object using wc_get_product(). If you’re on the frontend looking at a single product, then you can get the product ID from get_queried_object_ID().