Why are emails not sent to external domains?

Question

postfix

Hello. Raised postfix + dovecot, letters come, everything is ok. But for some reason, they are not sent to external domains, when trying to send, it gives out:
rcpt to: [email protected]
454 4.7.1 : Relay access denied
What is wrong in the config?

queue_directory = /var/spool/postfix
command_directory = /usr/sbin
daemon_directory = /usr/libexec/postfix
data_directory = /var/lib/postfix
mail_owner = postfix
myhostname = hostname
mydomain = dev.dev
myorigin = $mydomain
inet_interfaces = all
inet_protocols = all
mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain
unknown_local_recipient_reject_code = 550
mynetworks = 127.0.0.0/8, 192.168.0.0/24
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
home_mailbox = Maildir/
debug_peer_level = 2
debugger_command =
              PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
              ddd $daemon_directory/$process_name $process_id & sleep 5
sendmail_path = /usr/sbin/sendmail.postfix
newaliases_path = /usr/bin/newaliases.postfix
mailq_path = /usr/bin/mailq.postfix
setgid_group = postdrop
html_directory = no
manpage_directory = /usr/share/man
sample_directory = /usr/share/doc/postfix-2.10.1/samples
readme_directory = /usr/share/doc/postfix-2.10.1/README_FILES

Answer 1

Removed the line
Earned.

Answer 2

Try:

mydestination = $myhostname, localhost.$mydomain, localhost
relay_domains = $mydestination

or specify

relayhost=ip
#or
#relayhost=smtp.dev.dev