Jajjajaja,! Thanks but.. there are two or three problems :/
First. When the admin executes the plugin in the chat appears "[AMXX] Admin" and in the code i put "[AMXX Admin %s obligated %s"
In the console i put amx_desconfig without a name and the plugin works on me (i'm the first and the unique in the server) and if i put amx_desconfig max (my name in the server is MAXIIIIIIIIIIIIIIIII) in the console appears "Invalid user name", then i put my name complete and works.. :/