Dovecot cannot receive the email. Why ??

Dovecot cannot receive the email. Why ?? -- Linux general technology-Linux technology and application information. For details, refer to the following section. My account is postfix + dovecot + mysql certified. OE certification is no problem. I can send emails to the Internet, but I cannot receive emails from myself. I have found a lot of information, I have not understood it yet. It is very distressing. Please give me some advice. I will send the postfix and dovecot configuration files to see if something is wrong.
Dovecot configuration file:
Protocols = pop3 imap
Listen = *
Disable_plaintext_auth = no
Log_path =/var/log/dovecot. log
Info_log_path =/var/log/dovecot.info
Log_timestamp = "% Y-% m-% d % H: % M: % S"
# Ssl_disable = yes
# Mail_location = maildir:/% Lh/% Ld/% Ln/: INDEX =/% Lh/% Ld/% Ln/
Mail_location = maildir:/var/vmail/% d/% n
# Mail_location = maildir:/var/vmail/% d/% n
# Mail_location = maildir:/var/vmail/% d/% n/Maildir
# Default_mail_env = maildir:/var/mailbox/% d/% n
Mail_privileged_group = mail
First_valid_uid = 12345
Protocol imap {

}
Protocol pop3 {
Pop3_uidl_format = % 08Xu % 08Xv
}
# Protocol managesieve {## this is what I call it # It's Because dovecot can't do anything, so it's over. It's okay.
# Sieve = ~ /. Dovecot. sieve
# Sieve_storage = ~ /Sieve
#}

Auth default {
Machisms = plain login
Passdb pam {
}
Passdb SQL {
Args =/usr/local/dovecot/etc/dovecot-sql.conf
}
Userdb passwd {
}

Userdb SQL {
Args =/usr/local/dovecot/etc/dovecot-sql.conf
}

User = root
Socket listen {
Client {
Path =/var/spool/postfix/private/auth-client
Mode = 0660
User = postfix
Group = postfix
}
}
}


Postfix configuration file:

Command_directory =/usr/sbin
Config_directory =/etc/postfix
Daemon_directory =/usr/libexec/postfix
Data_directory =/var/lib/postfix
Debug_peer_level = 2
Html_directory = no
Mail_owner = postfix
Mailq_path =/usr/bin/mailq
Manpage_directory =/usr/local/man
Newaliases_path =/usr/bin/newaliases
Queue_directory =/var/spool/postfix
Readme_directory = no
Sample_directory =/etc/postfix
Sendmail_path =/usr/sbin/sendmail
Setgid_group = postdrop
Unknown_local_recipient_reject_code = 550
######################################## ########################################
Myhostname = mail.ludy.com
Mydomain = ludy.com
Myorigin = $ mydomain
Mydestination =
Mynetworks = 127.0.0.0/8, 192.168.1.0/24
Inet_interfaces = all
Home_mailbox = Maildir/
######################################## ####################################
Virtual_alias_maps = mysql:/etc/postfix/mysql/mysql_virtual_alias_maps.cf
Virtual_gid_maps = static: 33
Virtual_mailbox_base =/var/vmail ### virtual user directory
Virtual_mailbox_domains = mysql:/etc/postfix/mysql/mysql_virtual_domains_maps.cf
Virtual_mailbox_maps = mysql:/etc/postfix/mysql/mysql_virtual_mailbox_maps.cf
Virtual_minimum_uid = 123456 ### grant apache permissions.
Virtual_transport = virtual
Virtual_uid_maps = static: 123456
######################################## ######################################## #
Message _ size_limit = 52428800
Mailbox_size_limit = 209715200
Virtual_mailbox_limit = 209715200
Virtual_create_maildirsize = yes
Virtual_mailbox_extended = yes
Virtual_mailbox_limit_maps = mysql:/etc/postfix/mysql/mysql_virtual_mailbox_limit_maps.cf
Virtual_mailbox_limit_override = yes
Virtual_overquota_bounce = yes
######################################## ######################################## #
Smtpd_sasl_auth_enable = yes
Smtpd_sasl_type = dovecot ### define the installation method dovecot
Smtpd_sasl_path = private/auth-client #### the path must be the same as dovecot
Broken_sasl_auth_clients = yes
Smtpd_recipient_restrictions = permit_mynetworks,
Permit_sasl_authenticated,
Reject_invalid_hostname,
Reject_non_fqdn_hostname,
Reject_unknown_sender_domain,
Reject_non_fqdn_sender,
Reject_non_fqdn_recipient,
Reject_unknown_recipient_domain,
Reject_unauth_pipelining,
Reject_unauth_destination