The Virtualizor_Admin_API method should be __constructor, otherwise we have errors like the one below and it will stop working in a future version.
Quote
PHP error: Methods with the same name as their class will not be constructors in a future version of PHP; Virtualizor_Admin_API has a deprecated constructor in virtualizor.php on line 24
This is a very old style of coding so I'd appreciate if if you could update soon!