Interface in uvm_test

In reply to dave_59:

Hey Dave, I encounter the above scenario by using disable iff in assertion(in interface file) so that i can control in test cases by interface handle.

but i want to know why it not like Virtual interface ?

in my base test it’s virtual interface, i used that in test cases as $assertoff(lbus_if.cssss);
please suggest how to use vif in $asserton/off
Error: Fatal error (bad handle reference)