FTP Isolation

Hi, I am working on setting up FTP 8.5 in isolation mode. Following is the FTP site structure. Ftpuser04 can access ftpuser04 , ftpuser05 and ftpuser07 folders. When I connect as ftpuser05 or ftpuser07 I get 530-User cannot login, home directory inaccessible. Am I missing something or this is not doable?

Thanks

FTP site structure

ftp.test.com

                -LocalUser

                                -ftpadmin01

                                -ftpuser01

                                -ftpuser02

                                -ftpuser03

                                -ftpuser04

                                                -ftpuser05

                                                -ftpuser07

                                -ftpuser06

Permissions for ftpuser05 folder

 Allow ftpuser04                               read, write

Allow                       ftp Users          read

Allow                       ftp Admins        read, write

Allow ftpuser05                                                read, write