When I try to send an e-mail to an alias listed in /etc/postfix/aliases, it rejects me.

This is the log:
May 22 16:12:26 correo postfix/smtpd[3119]: NOQUEUE: reject: RCPT from localhost.localdomain[127.0.0.1]: 550 5.1.1 <policyd@xxx.com.uy>: Recipient address rejected: User unknown in virtual mailbox table; from=<test@xxx.com.uy> to=<policyd@xxx.com.uy> proto=ESMTP helo=<192.168.11.200>

My /etc/postfix/aliases file:
#
#  Aliases in this file will NOT be expanded in the header from
#  Mail, but WILL be visible over networks or from /bin/mail.
#
#       >>>>>>>>>>      The program "newaliases" must be run after
#       >> NOTE >>      this file is updated for any changes to
#       >>>>>>>>>>      show through to sendmail.
#

# Basic system aliases -- these MUST be present.
mailer-daemon:  postmaster
postmaster:     root

# General redirections for pseudo accounts.
bin:            root
daemon:         root
adm:            root
lp:             root
sync:           root
shutdown:       root
halt:           root
mail:           root
news:           root
uucp:           root
operator:       root
games:          root
gopher:         root
ftp:            root
nobody:         root
radiusd:        root
nut:            root
dbus:           root
vcsa:           root
canna:          root
wnn:            root
rpm:            root
nscd:           root
pcap:           root
apache:         root
webalizer:      root
dovecot:        root
fax:            root
quagga:         root
radvd:          root
pvm:            root
amanda:         root
privoxy:        root
ident:          root
named:          root
xfs:            root
gdm:            root
mailnull:       root
postgres:       root
sshd:           root
smmsp:          root
postfix:        root
netdump:        root
ldap:           root
squid:          root
ntp:            root
mysql:          root
desktop:        root
rpcuser:        root
rpc:            root
nfsnobody:      root

ingres:         root
system:         root
toor:           root
manager:        root
dumper:         root
abuse:          root

newsadm:        news
newsadmin:      news
usenet:         news
ftpadm:         ftp
ftpadmin:       ftp
ftp-adm:        ftp
ftp-admin:      ftp
www:            webmaster
webmaster:      root
noc:            root
security:       root
hostmaster:     root
info:           postmaster
marketing:      postmaster
sales:          postmaster
support:        postmaster

# trap decode to catch security attacks
decode:         root
# Person who should get root's mail
#root:          marc
virusalert:     root
root: test2@xxx.com.uy
policyd: test2@xxx.com.uy

My /etc/postfix/main.cf
alias_database = hash:/etc/postfix/aliases
alias_maps = hash:/etc/postfix/aliases
allow_min_user = no
biff = no
bounce_queue_lifetime = 1d
broken_sasl_auth_clients = yes
command_directory = /usr/sbin
config_directory = /etc/postfix
content_filter = smtp-amavis:[127.0.0.1]:10024
daemon_directory = /usr/libexec/postfix
data_directory = /var/lib/postfix
debug_peer_level = 2
delay_warning_time = 0h
disable_vrfy_command = yes
enable_original_recipient = no
header_checks = pcre:/etc/postfix/header_checks.pcre
home_mailbox = Maildir/
html_directory = no
inet_interfaces = all
inet_protocols = all
mail_name = iRedMail
mail_owner = postfix
mail_version = 0.4-stable
mailbox_command = /usr/libexec/dovecot/deliver
mailbox_size_limit = 15728640
mailq_path = /usr/bin/mailq.postfix
manpage_directory = /usr/share/man
maximal_backoff_time = 4000s
maximal_queue_lifetime = 1d
message_size_limit = 15728640
minimal_backoff_time = 300s
mydestination = $myhostname, localhost, localhost.localdomain, localhost.$myhostname
mydomain = tata.com
myhostname = correo.xxx.com.uy
mynetworks = 127.0.0.0/8
mynetworks_style = subnet
myorigin = correo.xxx.com.uy
newaliases_path = /usr/bin/newaliases.postfix
queue_directory = /var/spool/postfix
queue_run_delay = 300s
readme_directory = /usr/share/doc/postfix-2.5.6/README_FILES
receive_override_options = no_address_mappings
recipient_bcc_maps = mysql:/etc/postfix/mysql_recipient_bcc_maps_domain.cf, mysql:/etc/postfix/mysql_recipient_bcc_maps_user.cf
relay_domains = $mydestination
sample_directory = /usr/share/doc/postfix-2.5.6/samples
sender_bcc_maps = mysql:/etc/postfix/mysql_sender_bcc_maps_domain.cf, mysql:/etc/postfix/mysql_sender_bcc_maps_user.cf
sendmail_path = /usr/sbin/sendmail.postfix
setgid_group = postdrop
smtpd_data_restrictions = reject_unauth_pipelining
smtpd_enforce_tls = no
smtpd_helo_required = yes
smtpd_helo_restrictions = permit_mynetworks,permit_sasl_authenticated, check_helo_access pcre:/etc/postfix/helo_access.pcre
smtpd_recipient_restrictions = reject_unknown_sender_domain, reject_unknown_recipient_domain, reject_non_fqdn_sender, reject_non_fqdn_recipient, reject_unlisted_recipient, permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination, reject_non_fqdn_helo_hostname, reject_invalid_helo_hostname, check_policy_service inet:127.0.0.1:10031
smtpd_reject_unlisted_recipient = yes
smtpd_reject_unlisted_sender = yes
smtpd_sasl_auth_enable = yes
smtpd_sasl_authenticated_header = no
smtpd_sasl_local_domain =
smtpd_sasl_path = dovecot-auth
smtpd_sasl_security_options = noanonymous
smtpd_sasl_type = dovecot
smtpd_sender_login_maps = mysql:/etc/postfix/mysql_sender_login_maps.cf
smtpd_sender_restrictions = permit_mynetworks, reject_sender_login_mismatch, permit_sasl_authenticated
smtpd_tls_cert_file = /etc/pki/iRedMail/SSL_Cert.pem
smtpd_tls_key_file = /etc/pki/iRedMail/SSL_Key.pem
smtpd_tls_loglevel = 0
smtpd_tls_security_level = may
tls_random_source = dev:/dev/urandom
transport_maps = mysql:/etc/postfix/mysql_transport_maps.cf, hash:/etc/postfix/transport
unknown_local_recipient_reject_code = 550
virtual_alias_maps = mysql:/etc/postfix/mysql_virtual_alias_maps.cf
virtual_gid_maps = static:500
virtual_mailbox_base = /home/vmail
virtual_mailbox_domains = mysql:/etc/postfix/mysql_virtual_mailbox_domains.cf
virtual_mailbox_maps = mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf
virtual_minimum_uid = 500
virtual_transport = dovecot
virtual_uid_maps = static:500

Thank you in advance!!