Problem with username generator

I have tried it and it doesn’t work, maybe I am doing something wrong by doing it from the ISC plugin of Visual Studio. I set the name to “cloudLifecycleState,” which is an existing identity attribute. In “attributeName” within “identityAttribute” I am using “lastname,” which is also an identity attribute. After provisioning from the source, nothing is generated (it should display “@[corresponding_lastName]” but it shows the usual value):

I understand that even if I am not using the correct values, this is just a simulation to see if the information is created correctly and to learn how it works.

Thanks!