The system could not create the user error

hello, i have a problem when i try to create a new user i get error as below [QUOTE](XID xsdxxt) The system could not create the user "special" because it conflicts with an unmanaged MySQL database user. at /usr/local/cpanel/Whostmgr/Accounts/Create.pm line 1196.
even i have removed the user from everywhere and all databases everythings are erased can anybody tell me what to do to remove it please