User rule issue

I am trying to change the rule of the user

What do you call change the rule of the user? The function ? the profile ? the type of individuals? 

Invalid cont 
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 Wich page ?

rols.

what is this page?

Impossible to delete this element because of existing dependent elements
 - Ticket (39)

if you try to uncheck a box, like "is a resource" then it seems to work on the 39 tickets. You will not be able to. You will first need to close these tickets and not reassign work to this one.

If not that then your message is not clear enough.
try to explain more clearly with the correct vocabulary encountered in ProjeQtOr please