InaccessibleProperty

A private or protected property is read from a scope that does not have permission to read it. Private properties are only accessible within the declaring class; protected properties are accessible within the declaring class and its subclasses. This applies to both instance ($obj->prop) and static (Class::$prop) property access.

Example

<?php
class Vault {
    private string $secret = 'classified';
}

echo (new Vault())->secret; // cannot access private property from outside the class

How to fix

Change the property’s visibility to public, add an accessor method, or access it only from within the declaring class (or a subclass, for protected).