CentOS 7 Mail server error (User unknown in virtual alias table) Dovecot Postfix MySQL

postconf -n:
alias_database = hash:/etc/aliases
alias_maps = hash:/etc/aliases
append_dot_mydomain = no
biff = no
broken_sasl_auth_clients = yes
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/libexec/postfix
data_directory = /var/lib/postfix
dovecot_destination_recipient_limit = 1
html_directory = no
inet_interfaces = all
inet_protocols = all
mail_owner = postfix
mailbox_command = /usr/lib/dovecot/deliver
mailq_path = /usr/bin/mailq.postfix
manpage_directory = /usr/share/man
message_size_limit = 3000720000
mua_client_restrictions = permit_sasl_authenticated, reject
mua_helo_restrictions = permit_mynetworks, reject_non_fqdn_hostname, reject_invalid_hostname, permit
mua_sender_restrictions = permit_sasl_authenticated, reject
mydestination = mail.domain.com
mydomain = domain.com
myhostname = mail.domain.com
myorigin = $mydomain
newaliases_path = /usr/bin/newaliases.postfix
queue_directory = /var/spool/postfix
readme_directory = /usr/share/doc/postfix-2.10.1/README_FILES
relayhost = smtp.domain.com
sample_directory = /usr/share/doc/postfix-2.10.1/samples
sendmail_path = /usr/sbin/sendmail.postfix
setgid_group = postdrop
smtp_tls_mandatory_protocols = !SSLv2, !SSLv3
smtpd_recipient_restrictions = permit_mynetworks, permit_auth_destination, permit_sasl_authenticated, reject
smtpd_restriction_classes = mua_sender_restrictions, mua_client_restrictions, mua_helo_restrictions
smtpd_sasl_auth_enable = yes
smtpd_sasl_authenticated_header = yes
smtpd_sasl_local_domain = $myhostname
smtpd_sasl_path = private/auth
smtpd_sasl_security_options = noanonymous
smtpd_sasl_type = dovecot
smtpd_tls_cert_file = /etc/letsencrypt/live/mail.domain.com/fullchain.pem
smtpd_tls_key_file = /etc/letsencrypt/live/mail.domain.com/privkey.pem
smtpd_tls_mandatory_protocols = !SSLv2, !SSLv3
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtpd_use_tls = yes
transport_maps = *
unknown_local_recipient_reject_code = 550
virtual_alias_domains =
virtual_alias_maps = mysql:/etc/postfix/mysql_alias.cf
virtual_gid_maps = static:5000
virtual_mailbox_base = /home/vmail
virtual_mailbox_domains = mysql:/etc/postfix/mysql_domains.cf
virtual_mailbox_maps = mysql:/etc/postfix/mysql_users.cf
virtual_transport = dovecot
virtual_uid_maps = static:5000

doveconf -n:
# 2.2.36 (1f10bfa63): /etc/dovecot/dovecot.conf
# OS: Linux 3.10.0-1160.108.1.el7.x86_64 x86_64 CentOS Linux release 7.9.2009 (Core) xfs
# Hostname: mail.domain.com
auth_mechanisms = plain login
disable_plaintext_auth = no
first_valid_uid = 1000
listen = *
mail_location = maildir:/home/vmail/%d/%n
mbox_write_locks = fcntl
namespace inbox {
hidden = no
inbox = yes
location =
mailbox Drafts {
special_use = \Drafts
}
mailbox Junk {
special_use = \Junk
}
mailbox Sent {
special_use = \Sent
}
mailbox "Sent Messages" {
special_use = \Sent
}
mailbox Trash {
special_use = \Trash
}
prefix = INBOX.
separator = .
type = private
}
passdb {
args = /etc/dovecot/dovecot-sql.conf.ext
driver = sql
}
service auth-worker {
user = root
}
service auth {
unix_listener /var/spool/postfix/private/auth {
group = postfix
mode = 0666
user = postfix
}
unix_listener auth-master {
mode = 0600
user = vmail
}
user = root
}
service imap-login {
inet_listener imap {
port = 143
}
inet_listener imaps {
port = 993
ssl = yes
}
}
service lmtp {
unix_listener /var/spool/postfix/private/dovecot-lmtp {
group = postfix
mode = 0600
user = postfix
}
unix_listener lmtp {
mode = 0666
}
}
service pop3-login {
inet_listener pop3 {
port = 110
}
inet_listener pop3s {
port = 995
ssl = yes
}
}
ssl = no
ssl_cert = </etc/letsencrypt/live/mail.domain.com/fullchain.pem
ssl_key = # hidden, use -P to show it
userdb {
args = /etc/dovecot/dovecot-sql.conf.ext
driver = sql
}
userdb {
args = uid=vmail gid=vmail home=/home/vmail/%d/%n
driver = static
}
protocol lda {
auth_socket_path = /var/run/dovecot/auth-master
log_path = /home/vmail/dovecot-deliver.log
postmaster_address = postmaster@domain.com
}
protocol pop3 {
pop3_uidl_format = %08Xu%08Xv
}

I'm encountering an issue with my mail server configuration on CentOS 7. Specifically, I'm unable to send emails to remote mail servers such as Gmail or any other domain. Initially, I included transport_maps, but encountered a "user unknown" error. To address this, I added transport_maps = hash:/etc/postfix/transport, which resolved the issue with Gmail by specifying gmail.com smtp:[smtp.gmail.com]:587. However, this fix only applies to Gmail, and I still cannot send emails to other domains like user@domain.com, .org, or .net.

Locally, I can both send and receive emails without any problems. However, the issue persists when attempting to send emails remotely...