'__asd_subtenantRef' is not working

Hello, I have a virtual machine blueprint in my vRA enviroment.

I'm traying to use the following script to get the business group from the user who request the catalog item.

var tenant = System.getContext().getParameter("__asd_tenantRef"); // This works fine

var bg = System.getContext().getParameter('__asd_subtenantRef'); //This show the error

But vRA shows me an error, and i dont know why....what is wrong?.

I hope help from you.

Best regards,

Eric.