Using "entity exists" or other condition to check user existence

I'm trying to check user existence, having a condition like:

NOT Entity exists by property
Parameter: Entity type: User, Property: mail, Value: {provided-data}

(action should be taken if user does NOT exist, and where {provided-data} is a valid replacement pattern)


I'd like to check that there's no user with a "{provided-data}" mail... it doesn't work and I think it's not the way it's supposed to work, maybe... is it so? And there's another similar condition to check "name" property too.

How can I achieve it? thankx