[Maxximou5]

That isn't the issue, you need to configure your server FTP program.
Such as: vsftpd, Pure-FTPd, ProFTPd, or iFTPd.

What you need to do is chroot the user to a directory. If you don't manager your own server and have access to this, you're going to be out of luck. Unless of course your GSP is willing to do that for you.